From Russia, Moscow to Vladivostok, remained in one piece to eventually become part of the Soviet Union. How?
How was the new government able to get control of such a huge area in such a short time? Did they lose and later regain control of parts of siberia or elsewhere?
Well, to put it simply, they didn't gain control of the whole of the country that became the Soviet state in what I would call a short amount of time, and the USSR never controlled the entirety of the former Tsarist Empire.
When Lenin seized power he was essentially limited to the area surrounding/between Moscow and Petersburg, with the relatively underdeveloped Russian rail system as the only means of projecting power beyond the indurial centers. Everywhere else people were either left to their own devices, something most villages preferred anyway and were quite used to since the tsarist state never properly developed instruments of central control over the periphery, or, increasingly, subjected to one of the new 'governments' that either opposed the Bolshevik takeover in the quickly developing civil war or simply filled a local power vacuum.
These new centers of power ranged from the independently-operating forces collectively known as the Whites, a movement for restoring the tsarist state based in the Caucasus, Urals and around Arkhangelsk, to Cossack Hosts seizing the opportunity for independents, to the Black Army of Nestor Makhno and the anarchist Free Territory they established in the Donbas - and those are just the significant military forces. Sovnarkom (the Bolshevik government) didn't completely stamp out armed resistance in the Far East and Central Asia until 1923-24.
As to how the Soviets won the civil war, it's been argued that the combination of controlling the only major centers of production and population, the focal points of the rail network, and facing an enemy that the people had no reason to support made success, barring a Western intervention, basically inevitable. The only chance the counterrevolution had was right after the Bolshevik coup, before power was effectively consolidated in the core. No one else was operating from a base strong enough to field a force that could challenge the Red Army after 1919, but the geography and logistics at play meant that it still took a long time for the Red Army to finish the war.