To make a backup of your server, head to the backups page under the tools
To make your backup, press the create backup button
You should see a page like this
The first box is the name of your backup, the second is the files you want to be ignored.
So if you would like to backup everything apart from your world file. You can just put world here, and it will be ignored in the backup.
The lock stops the backup from being deleted until it’s unlocked. This is helpful if you have a backup running on a schedule.
Once the backup has been made you can restore it, or download it by pressing the three dots
Pressing the restore button will fully restore the backup to your server overriding any newer files.