How to make multi-level game with one scene? Will it give rise to new bugs?

Hi, I'm trying to make my 2d game lightweight, so I've decided to go with a single game scene for all the levels. If this sounds stupid then give me some tips on how to reduce my game's size
Thank you.

 

well, isnt stupid if you are willling to do some king of infinity runner, but it isnt a thing when you are trying to do, a.. normal game, so, if you really wants to do it, put some kind of door where you cant go back, and destroy everything that is behind it, you can after that try to put the spam of instances in direction of the center of the scene again so the transforms dont overload anything