iPad 2020 storage

Hello

I have problems with my iPad storage.

Firstly, is it normal that Google Drive files take space on my iPad?

Secondly, sometimes when I check storage info, it is shown that there a lot of files in Files app, but when I open it, I see that maybe 500 MB is used. Is it an iOS problem that storage information is wrong?

Please somebody help! :)

It is really annoying that I should often delete apps and files to save at least a little bit of space on my iPad