Remove strange code from wordpress footer [closed]

There is a WP hack (probably several) that will modify the footer, usually by modifying the active theme code. Completely delete that theme (via your hosting File Manager), then reinstall the theme from the WP repository.

And, since your site was hacked, there are probably (most likely) other areas of your site that need to be ‘de-hacked’. Lots of help on the googles (and here, although hacked sites is not within allowable questions here) on how to de-hack a WP site.

Change all credentials (hosting, ftp, WP admin, database); inspect all files for added code, reinstall all themes/plugins from known good sources, update everything, and more.