How can you set the camera to follow your chose of actor or object?
Use a Spring Arm Component:
https://docs.unrealengine.com/latest/INT/API/RuntimeModules/Engine/GameFramework/USpringArmComponent/index.html
Also, check out the Third Person template, to see how the camera is attached to the player character.
Thanks for that but I cant program I was hoping for blueprint tutorial. but I could learn programming if I know were to start and know all the program that I need to know to make a unreal game. but thanks
You can do the same thing in Blueprints. Did you check out the Third Person template project?