1. Press ⊞ Win + R on your keyboard.
2. In the Run window, copy/Paste %APPDATA%\..\LocalLow\IronGate\Valheim\worlds_local

3. Navigate to\LocalLow\IronGate\Valheim\worlds_local (also check worlds folder)
4. Find the .db and .fwl file with your worldname.

0. Stop the server
1. Open the File Manager

2. Navigate to /.config/unity3d/IronGate/Valheim/worlds_local/
3. Put both the .db and .fwl files in this folder.
4. In the Basic Server Settings, set the World Name to match the name of the .fwl and .db files.
5. Save and restart your server and the save will be loaded onto the server.