i want to apply for this study this year but i dont really know what i need to put in my portfolio since i didnt draw a lot etc. and the things i made i didnt save.

Your portfolio can contain any creative (tech) work you have ever made. Drawings, 3D models, attempts at coding, whatever fits with the study. It mostly depends on what kind of role you want to choose once you start studying. It's important to explore this before starting the study so that you are confident in your choice.

CMGT will turn your hobby into a skill used in a workfield. This is why you need to be careful with it. IF you end up liking the game development process when making your intake assignment or putting things in your portfolio: great! That means you have the drive for interactive tech development. But if it turns out you just like the idea of it, and don't really wanna dive into the things you're gonna learn already, then you should maybe reconsider your study choice.

Play around with 3D, code a bit, do some designing and concepting. All of these things are key to finding your place in the creative technology industry. And the sooner you figure that out, the better.