To get LiveProfessor to do something useful, you need plugins.
The supported plugin formats are VST2 & VST3 on Windows and VST2, VST3 and AudioUnits (AU) on macOS
​More information on plugin formats can be found here

LiveProfessor will run natively on the Apple Silicon CPU where available. If the plugin is incompatible with Apple Silicon, it will fail to load, as the plugin and the host (LiveProfessor) must run under the same CPU architecture.

MacOS should handle this converting on the fly for AU plugins, so you should not need Rosetta for these.

To use other non-compatible plugins and run under Rosetta, right-click (or ctrl+click) on the LiveProfessor application icon and select Get Info, then enable the Open using Rosetta option.

The entire application and all plugins will then run under Rosetta.

Assuming that you have downloaded and installed the necessary plugins per the creators' instructions, the next step is to inform LiveProfessor where they are located.

Open the Plugin Manager Window by going to the menu Options > Plugin Manager.

Click the Look for new plugins - button to add new plugins.

In the popup menu that follows, select the desired plugin format.
Make sure all license dongles etc., are connected when scanning starts.

The Plugin Scanner will now look through the standard plugin folders on the computer for compatible plugins, do a basic test, and add them to the list. If there are many plugins installed, this process can take a while.

You may also see popup windows for license activations and other plugin notifications.

If the scanning should fail because of a misbehaving plugin, the scan will restart, and the problem plugin will be skipped.

Once the scan completes, you should see the full list of installed plugins

More details on the Plugin Manager Window can be found here