Filezilla File Moved – WP down

Dear all,

I guess I have a really stupid question on a very stupid problem.

I have a domain from 1&1 and my webspace at 000webhost.com. I loaded everything up with filezilla into a folder named wordpress.
But this gave me on the domain page just *index -wordpress. If I clicked there on wordpress this gave me https://www.mydomain.xy/wordpress, where everything was nicely working. But I didn’t like the /wordpress after my domain name, so I decided to move the whole stuff out of the wordpress-folder into the public folder, hoping this would solve the thing. Of course it didn’t , permalink change try changed did not work, so I decided to move via Filezill, back as it was.
But now, I can type https://www.mydomain.xy/wp-admin and can login but not change anything, when I click for example “Setttings” I am immediately directed to the Errorpage of 000webhost.

What did I do wrong? How can I solve the problem? or was all my work on my homepage for nothing?

please help me…!