I installed the plugin "yoast seo" and now when I enter and exit, they give me an error. And I can only come through /wp-login.php. how to fix ? please help
...what @sally_CJ said in the comment to your question.
In general, if a plugin is causing problems, then remove the plugin. If you can't do that with admin/plugins, then use your hosting File Manager or FTP to rename that plugin's folder, which will effectively disable it.
Also, ensure that PHP is at least version 7.2, and ensure WP and all themes/plugins are updated.