Error in Wordpress on the Admin panel

Question

Personal developed a site with Wordpress that can be seen from this link but when accessing the wp-admin appears this error what can be:

OBS: I installed a plugin quiz was stirring normally and out of nowhere came this mistake

Answer 1

I advise, first, uninstall the plugin for the page back to run in production.

As you are without access to the admin panel, delete the folders related to the plugin and then check for traces of the plugin in your database.

Check if such a plugin is compatible with your WP version before reinstalling it.