How to make a admin on Factorio server
Adding Admin via console.
Log in to the Kinetic Panel.
Start the server.
Open console.
In console put
/promote username
Replace username with the username of the player.
Enter the command & the user will be an admin.
Adding Admin via Files
Log in to the Kinetic Panel
Navgaite to file manager.
Open server-adminlist.json
Enter the user's name surrounded by quotes.
Save the file.
Restart the server.