Who are these two men?

Vladimir Komarov and Yuri Gagarin.

Gargarin, a Soviet test pilot and Cosmonaut, was the first human to journey into outer space, when his Vostok spacecraft completed an orbit of the Earth on 12 April 1961.

Komarov was a Soviet test pilot, aerospace engineer and cosmonaut in the first group of cosmonauts selected in 1960.

His spaceflight on Soyuz 1 made him the first Soviet cosmonaut to fly into outer space more than once, and he became the first human to die on a space mission—he was killed when the Soyuz 1 space capsule crashed after re-entry on 24 April 1967 due to a parachute failure.

Young Vladimir Lenin and Leon Trotsky?

Lenin masterminded the Russian Revolution in 1917 and became the first leader of the Soviet Union, while Leon Trotsky was Marxist revolutionary and worked with Lenin during the Russian revolution and the establishment of the Soviet Union. He was later assassinated on the orders of Stalin in Mexico.

Felix Dzerzhinsky and Vladimir Kryuchkov?

Dzerzhinsky was the founder of the KGB, and Kryuchov was the last head of the KGB before it was disbanded in 1991 after he led a failed coup. The two men never met.

Nikolai Budarin and Vladimir Dshurov? Fictitious names.