Changing links

I’ve started to work on a french website and I’ve ran into a few issues.
1. WordPress was automatically installed by the hosting provider and it was not in utf8_unicode_ci, I’ve changed that from phpmyadmin.
2. I wanted to add french characters to my links from the WordPress dashboard, I wouldn’t allow that. I found a solution online to change it from the tables in PHPmyAdmin but after I change it, it changes everywhere on the site, which is good, but when I hit update on a page it reverts to the previous state. How can I make these changes permanent?