FTP – Connection & Directories

Hello,

I recently got control over a WP Page somebody else made. The Problem is that WP keeps asking me for my FTP credentials every time I want to upload something. It says:

“Unable to create directory wp-content/uploads/2020/11. Is its parent directory writable by the server?”

or:

“Unable to locate WordPress plugin directory.”

or:

“Unable to locate WordPress theme directory.”

I have already changed the ftp credentials a few times – didn’t help.
I also resetted WP with the plugin WP-Reset.
I tried to delete and re-upload the WP Files via C-Panel – didn’t help.
I tried to modify the wp-config file – didn’t help.

What else can I do, HELP!
I asked the host provider but they told me they don’t klnow what to do BUT they gave me access to c-Panel, so i can do everything without having to use Filezilla(I think)

The page I need help with: [log in to see the link]