Hallo fellow Vikings
To upload your save files to the server you first need to find them on your local computer. The default location for them would be in Appdata\locallow\irongate
There you will see a folder called world and inside should be 2 files, a .DB file and a ,FWL file both you need to upload to your server.
To do this open TCadmin, go to File Manager then open the Saves\Worlds directory and upload those 2 files in there.
Once you have uploaded the files you need to go to Comamndline Manager you need to click on SELECTED and make sure your WORLD name is the same as your save files name. So if your save files is called Valheim it should look something like this.
Once done, start your server and it should work.