Help, collisions are difficult

It’s extremely hard and it takes very long to create a level by duplicating scenes in my games, because i have to make the collisions work (the collisions only use the past object not the present one) ALL AGAIN each level i make, how do i fix it?
If you don’t get it, here
I duplicate the scene
Instead of the collision selecting the present object it selects the object from the previous scene


hi sry i wish i could help but idk abt this stuff sorry again