So I can talk about this in relation to Stalin and his numerous stints in exile, so this will be speaking of the late Tsarist period only:

There seem to be different degrees of exile depending on the circumstances for his first sentence Stalin was sent to lands in East Siberia however this camp was sufficiently close to villages and railway lines that he would escape within 2 months (arriving in Nov 1903 but reappearing in Tiflis/Tbilisi in January '04) he was caught on his first attempt after nearly freezing to death though.

So in this case the camp was close enough to civilization that escape was possible - albeit many suspected he had been assisted in this escape.

His second stint was, again, at a camp close enough to villages/rails he would escape before being sent back, having affairs with women in the local village before before being allowed to move to a city, having more affairs, escaping and being sent back to the city again!

That is to say exile seemed to really be a case of just getting people out of the way more than anything, however his final stint in exile would be a bit different:

Instead of towns along the west-east rail lines he was sent to the far north east of siberia in Turukhansk. Even whilst there he would be moved to more remote settlements further north to prevent possible escape. The most remote of these was accessible only in the summer months and had no road connection.

From what writings we have of Stalin, and other revolutionary's experiences, is that these weren't labour camps nor was there any punishment beyond your isolation. Afterall these exiles would write essays and letters back to their revolutionary partners, Trotsky would criticise Stalin for his lack of writings during the great war whilst he was exiled for example, and indeed letters would be sent with what seem (to me at least) as very open discussions on anti-Tsarist topics.

From his writings we can conclude the overriding feeling for exiles was extreme boredom. In every letter he would beg the recipients to send books and talk of the crippling boredom/isolation. Whilst in the far north he seems to have spent much of his time fishing with the indigenous Siberian people's that lived nearby, reading books and (still, somehow) managed to find a girl to have an affair with.

In 1917 these revolutionary exiles would even be conscripted (which, to me, is frankly mental when your army is already mutinous but that's the Tsarist regime for you) so all in all I think it's fair to say these camps weren't terrible and were merely places to keep troublemakers for awhile

In summary: the only work would have been to build shelters, if needed, and maybe collect firewood. Inmates appear to have been given plenty of leeway to just go off and do stuff but the real punishment was the harsh weather, and distance to the Russian core. As for what stopped people escaping, and from the above you can probably tell, not a lot! Albeit you could easily be caught boarding a train etc if they knew you were gone

Sources: Montefiore, Simon Sebag (2007). "Young Stalin"

Kotkin, Stephen (2015). "Stalin vol I: Paradoxes of Power"

Edit: grammar changes and tweak to summary

Life in the Siberian exile system varied somewhat widely over the course of the autocracy's control over the region. But in general, life under Siberian exile was pretty harsh with high rates of disease and correspondingly high death rates.

The Siberian exile system as it evolved after the Napoleonic Wars tended to use Siberia as a loose dumping ground for prisoners. These prisoners could range from the poorest indigent serfs to political prisoners such as the Decemberists, some of whom were from the upper echelons of imperial society. Exiles often had to make their way to Siberia by foot and at times in chains, although this latter requirement tended to give way once the exile crossed the Urals. Clothing, food, and other necessities were often in short supply on the way to exile. The tsarist state nominally would provide these sundry items but in practice, exiles were often expected to organize their own survival. One of the dominant features of the travel into Siberia was the organization of various artel, or organizations, of prisoner groups in which there was collective ownership of property. While the arteli at times fueled Romantic notions of a collective, in practice, arteli were highly exploitative. Women traveling with their partners in exile soon found themselves relegated as common property as the Siberian exile system had a profound gender imbalance. Exiles often found themselves in a social world that put a premium on survival and an artel was a harsh method of ensuring survival.

Once the exiles arrived at their designated site of exile, some were put to work. A large number of the Decemberists, for example, had to work the mines at Nerchinsk. This was often quite dangerous labor. Likewise, food was often quite scarce within the exile colonies and the exiles had to often organize their own food. This was one of the reasons why hunting and fishing appears so prominently within exile memoirs. Mandatory labor requirements of the exiles eased somewhat throughout the nineteenth century, but the labor conditions were seldom easy. Criminal exiles often had to arrange for their own living conditions, as the state often lacked the resources to do so. This became doubly true after an exile's penal service ended as they were legally unable to return to European Russia.

One of the biggest problems of the Siberian exile system was that the tsarist state was actually rather undergoverned and bureaucratically weak despite its pretensions to autocracy. Exiles found themselves bounded in by a state that was more or less strong enough to keep them within Siberia, but could not be an adequate warden for the exiles. Exiles often found themselves within Siberia forced to engage in labor that made little sense from a developmental point of view so that they remained sedentary settlers in a landscape that was not conducive to such a settlement. The late-nineteenth century saw efforts to reform the exile system, but the same problems of undergovernment and lack of funds emerged. The most infamous case of this misplaced reformism was the penal colony of Sakhalin in the 1880s and 1890s. The island could barely support a fraction of the exiles and the island became a byword in tsarist educated society for all sorts of debauchery ranging from murder to child prostitution. The Sakhalin colony limped along despite various exposes on its living conditions until the Russo-Japanese War. The war prompted an evacuation of the colony, which in a fashion all too typical of the Siberian exile system, in which some 7600 men, women, and children were dumped on the bay opposite of Sakhalin and had to trek on foot to the nearest settlement, which was sixty kilometers away.

The above picture is somewhat at odds with the stereotype of various Bolsheviks' experience with exile. Lenin, for example, complained of the lack of books and Stalin made multiple escapes from his exile. Critics of the Bolsheviks, both then and since, have made much of this supposedly light exile, especially in light of how the Gulag system under Stalin managed to eclipse its tsarist predecessor in terms of harshness. But such criticism not only misses the point, but it also distorts the historical record. For one thing, the Bolsheviks entered into the exile system comparatively late in its existence. The transsiberian rail system considerably eased some of the problems of supply and increased the potential to escape. But the political exiles of the late-tsarist period were, like the Decemberists before them, a comparative elite within imperial society. They had preexisting networks which they could take advantage of both within the exile system and outside of it. The extreme inequities within the exile system tended not to touch this group.

Indeed, their (often indirect) experience with the harshness implicit to Siberian exile system arguably fueled the political exiles' desire to overthrow the autocracy. Contemporaries would contend that Siberian exile was one of the many problems of tsardom. Such critics were not limited to political revolutionaries like the Bolsheviks and included such figures as the American explorer George Kennan (a distant cousin of the American diplomat) and Mark Twain. The mortality rates within the exile system, and the tsarist prison system as a whole, were quite high, a fact used disingenuously by some post-Soviet defenders of Stalin to rehabilitate the USSR. But the later crimes of the USSR should not obscure the immense suffering, inequities, and death the tsarist Siberian exile system created.

Sources

Badcock, Sarah. A Prison Without Walls?: Eastern Siberian Exile in the Last Years of Tsarism. Oxford: Oxford University Press, 2017.

Beer, Daniel. The House of the Dead: Siberian Exile Under the Tsars. London: Allen Lane, 2016.

/u/Noble_Devil_Boruta has previously answered How hard was it to escape czarist Siberia?