Step 1:
Ensure to stop your server before proceeding with any of the following steps. You can do this by navigating to your TCAdmin panel and clicking 'stop' on the service.
Step 2:
Navigate to 'Mod Manager' which is found on the dashboard of your TCAdmin panel.
Step 3:
Click install on 'Oxide' (This needs to be installed if you wish to install RustIO or any other plugins).
Oxide is now installed!