Hi Elias,
Normally backups are restored through the WordPress admin, but fortunately Total Upkeep has a Command Line Interface that you can use via SSH to run backup restorations if the WordPress admin is inaccessible.
We have some documentation in the Total Upkeep repository that outlines the available commands that you can use to restore a backup over SSH that should be a useful reference for.
I hope that helps you get your website restored and please let us know if there is anything else that we can do to assist you!