Did the leaders of the Russian revolution keep their promises?

Answer 1

To a point.

If you take the three popular slogans as the promises ("Power to the workers, land to the peasants, peace to the peoples"), then workers did become the most celebrated and nominally ruling class, although the true power belonged to the Communist elite, army and secret police, the land was taken away from the landowners and wealthy peasants and converted into collective farms for all to work on and benefit form, though not to own, and Russia did pull out of WWI, but a bloody Civil War broke out immediately followed by years of Stalin's rule of terror.