Over one million women were in the Red Army during the 'Great Patriotic War', and unlike the West where they mostly volunteered, 3/4 of them had been conscripted. They were not only used in positions such as clerks, drivers, nurses, and radio operators, but saw actual combat. We see tankers, pilots, soldiers, and of course snipers utilized by the Red Army in direct combat with the enemy (although yopu had to volunteer for such a position, not be conscripted and forced in).

The "Night Witches" (588th Night Bomber Regiment) is quite well known as for being an all-female bomber regiment, gaining their names from their femininity, as well as the slow, quiet Po-2 bombers that they would glide in on at night to strike the Germans unawares. They were part of the all-female 122nd Air Group, which also included a Fighter Regiment (586th) and a second bomber regiment (587th). There were also air units that had mixed gender makeup, such as Lydia Litvak, a fighter pilot with the mostly male 73rd Guards Fighter Air Regiment.

A rather forgotten unit, part of the Soviet backed First Polish Corp/First Polish Army, was the Emilia Plater Independent Women’s Battalion. Raised in 1943, the 1,000 or so women were trained for combat, but an unwillingness on the part of their commanders to commit them meant that they ended up serving as sentries, MPs, and guarding POWs through the war. I don't know of any all-female ground unit that fought in combat with the Soviets.

I don't know how extensive their numbers were, but as tankers, women would usually serve as drivers. Originally they had been used to drive the tanks from the factory to the railyard to transport to the front, but with numbers of trained men running thin, many were allowed to volunteer for the front. The most famous woman tanker though was a 39 year old widow, Maria Oktyabr'skaya, whose husband was killed in 1941. She managed to save up her wages to sponsor a tank (not uncommon, although usually it was factories and collectives doing the sponsoring) while working as a tank mechanic, and was able to become a driver in the fall of 1943. She fought for a few months, before being injured in combat and later dying of her wounds in March of 1944.

As snipers, the small stature of women made them very well suited to the clandestine nature of their work, and it was believed that women had more patience than men, making them ideal for the role. Lyudmilla Pavlichenko was credited with over 300 kills, making her one of the most successful snipers of all time (although Soviet kill counts are notoriously unreliable, since they were a popular propaganda tool).

As nurses, women would be on the frontlines (in comparison to the other countries where female nurses were in the rear), under fire with the men. The Soviets took a loose view of the Geneva Convention, so these nurses would often be armed, and expected to fight if the situation got desperate! They were known as "myedsyestra", or medical sister, to their comrades. If a wounded soldier managed to survive long enough to get to the rear, he might also be operated on by female doctors, which were relatively common for the Soviet medical service compared to elsewhere.

The Soviet Navy was the service to use women least, and they generally were not allowed on warships, instead filling auxiliary roles on land.

There is of course a darkside here though. The Red Army was a hyper-masculine environment, and women in the Red Army were often treated very, very poorly. A pretty woman would almost certainly find herself 'taken under the wing' of an officer, and become his mistress. These were called "Polevaya Pokhodnaya Zhena", or in a pun on the PPSh submachine gun, "PPZh". This translated to 'mobile field wife'. Being a PPZh of course had perks, so of course earned further enmity of the male soldiers who would see them as sleeping their way there, even if they had little choice in the matter. Zhukov, who had taken Lida Zakharova as his 'field wife' (his third, and longest lasting, as they continued the affair several years after the war), spoke out against the practice, not because he was against it per se, but because he believed many officers neglected their real duties to hang out with their women. After the war, a woman who wore the Military Service Medal, "za boevye zaslugi", was disparagingly said to have earned the "za polevye zaslugi", or Sexual Service Medal.

(For those getting deja vu, yes this is a reworked answer from way back)

Sources

Ivan's War by Catherine Merridale

World War II Allied Nursing Services by Martin J. Brayley

World War II Allied Women's Services by Martin J. Brayley

Women at War 1939-45 by Jack Cassin-Scott

Women and War: A Historical Encyclopedia from Antiquity to the Present edited by Bernard A. Cook

/u/Georgy_K_Zhukov has said everything I wanted to write, but I would also recommend a book by Svetlana Aleksiyevich, War's Unwomanly Face. It's a collection of interviews with Soviet female soldiers of WWII.

Some examples of their experiences not mentioned in the top post: lack of female underwear in the army so they had to wear men's boxers, lack of sanitary products so they had to steal linen or risk blood and uterine tissues dribbling down their legs as they marched, lack of boots that fit, so their feet were blistered and aching. And finally, post-war attitude towards them, their own mothers treating them as fallen women.

I would recommend Anna Krylova's work, which certainly gets at this. She is one of the best of the new generation of Soviet historians.