Open the Templ Panel and click on your website that you want to access the database for.
Click on the Connect button in the top right corner, then click on DB Admin in the dropdown.
The details to login to Adminer are not needed to be entered manually. Click Login without changing any details and you will be logged in to the database automatically.
That's it. Now you should be a logged in to the database.
We strongly recommend creating a backup before you do any changes to your database, and/or testing your changes on a staging site first.