Welcome, Bapinurnose!
Yes, they can.
Ok, I know that if I’m the UK, and conquer FIC, I can’t place my planes there on the same turn I counquered it. But what if i’m the UK and I liberate Caucasus from the russians with two planes, can I land them there? (I’m asking this because on the turn it’s LIBERATED territory, not a newly conquered territory) Can I? Or do the same rules apply from conquering it on the same turn, that I can’t land the planes…
OK, UK would not be liberating it FROM the Russians, it would be FOR them.
On the turn that UK liberates Caucuses, the UK cannot land their FIGs there. However, later in the same turn, the United States CAN land FIGs there.
The restriction is that to land a FIG in a territory, the territory MUST have been controlled by you or one of your allies at the begining of YOUR turn.