Project clean up / file deleting question- need advice on lessening cpu load

Cubase Pro user- Im looking to clean things up bit on my first big cubase project. Ive used the “backup project” function to move the project to my backup drive and work on it from there.
im afraid to do anything I can’t come back from and im unsure about using the clean up function, or deleting stuff from the pool .

freezing isn’t always enough, and im at a point where everything is comped- but I really have a rediculous amount “takes” on this song

My question is , that I don’t know if I can use these functions like clean up or delete unused files, without doing it to ALL of the projects.
Does it delete the files themselves from the computer? because then it wouldn’t be worth it…chances are, ill find some snare hit or something that drives me nuts and I won’t be able to go back to all my takes because they will be gone

I just need a safe way to thin out the “backup project” a bit, that doesn’t have anything to do w freezing, or changing the sample rate /buffer size or anything like that
Solutions that won’t put me in a bad place later IF I need to access those files