How to use Workshop Map to your Team Fortress 2 Server
Login to the Kinetic Panel.
Stop the server.

Open File Manager.

Follow How to use Cycle Map.
At the top of the page, add workshop_(id)
Replace id with the Steam Workshop ID.
Save the file

Start the server.

If you want to change the active map to a modded map in the console on the panel, enter changelevel workshop/(Id)
Replacing the id with that maps id.