BuddyPress.org

It sounds like you could have a theme conflict. Your screenshot is gone, though, so I am not sure.

BP uses the WP login, so you should be able to log in to WP as before. Just visit your-site/wp-login.php

Here’s one way to do that: https://codex.buddypress.org/getting-started/guides/change-members-profile-landing-tab/

Hi, it sounds like you are clicking on the navigation item to get you to the edit screen. Below the form, look for a button labeled “Save Changes”.