Do you have a rulebook?
Because there’s no point in explaining the same thing to you as what’s in the rulebook if you already have a rulebook and don’t quite get what it’s going on about anyways.
Anyways, hopefully this will not be too confusing for you.
1. Purchase units
2. Combat Movement
3. Combat
4. Noncombat Movement
5. Place Units
During Combat Movement, you moved in “all land units” from two Russian territories. This means your Russian territories are now unoccupied.
You did not retreat during Combat. Your attackers survived, the defenders did not, as you specified by saying you ended up “winning”.
Since your land units have moved during the Combat Movement Phase, they cannot move during the Noncombat Movement phase. Their movement is over. They stay in the newly occupied, or as you put it, “won” territory.
Of course your “originating territories” are undefended. You moved everyone out. You could move any units you did not use in combat into either or both of those territories during noncombat.
Of course you don’t have to use all your units when attacking. Why would you even think that? It’s the voices isn’t it? Yes, they talk to me too. They tell me to do things. Sometimes the voices make me sad, or even angry. But it’s OK.
As you probably know, you can’t land air units in a newly occupied territory; such air units have to move during the Noncombat Movement phase to a territory that was controlled by you or your allies at the beginning of your turn (BEFORE Combat Movement), or must move to a sea zone that has an open spot on a carrier; this may include a carrier that you have newly placed. (and only fighters can land on carriers of course)
