How posses pawn in c++?

I want to allow charcter to take control over vehicle, when player press button, like in gta. I made pawn for vehicle and custom playercontroller, but i don’t know how to call Posses function. To be more specific I don’t know how get reference to pawn class, and where put this code?

But you detect player entering the vehicle right? You should get pointer to vehicle when that happens and use it to possess it, you can also make vehicle it self raport itself to player controller when player enters it. Tehre countless way how you can do this.