Ways to remove unnused RAM and Memory

[NewbEgg]

I got 500 gigs and 400 is being used and theres nothing on my programs file taking that up.. where do I look? cleaners dont help. Also Im not sure if this is a thing but can ram be like.. clogged or some sort?

 

[gangrel]

https://www.jam-software.com/treesize_free/

This will scan your drive and report usage, by default by the largest folders.