My wordpress files size keep increasing

Hello Everyone, Firstly Ramadan Mubarak to all muslim brother and sisters.
Its glad to be part of this community

I have a question
I am using google cloud with 30 GB size.
I have several wordpress websites and file size keep increasing i dont know why ? I have found some backup files and i delete it but not enough for open spacing in my drive

For example in this screen shot. this website 4113MB but when i go to public_html and download it its only 600 MB size. How is that possible.

all websites using %70 of disk but, actually all websites size must be %30 of disk

is this caused by cache or something ?
If anyone help with that i ll appricate it.

thank you

Ramadhan Mubarak

Look out for backups under /home/

Thank you Joseph,
Yes i deleted and its down to %58, is there any place i should look up ?

thank you

Wordpress cache files, .trash, other folders in /home/