Can’t access site, Big help needed

Hi guys, this is really my first time using WordPress, I normally just upload straight code to the server, after adding a few plugins and themes, my website seems to be having an error, I don't have access to the email associated with the account. I tried login in using mysitename/wp-login.php?action=entered_recovery_mode, and I'm getting the same error of

There has been a critical error on this website. Please check your site admin email inbox for instructions.

I made sure to make a backup before I did anything and have a wpress file available. The current website is completely broken and not sure what to do, my boss is going to fire me if he finds out 😭😭.