You don't say what you're trying to do. I use a Roland FC-300 foot controller. Connect to the computer with a MIDI IF, in your case an IF cable. In Edit preferences select it under MIDI -> Devices -> Input. Create a MIDI track, select your MIDI IF as the track input and select echo on. The fcb1010 is popular with guitarists. If you have an amp sim on an audio track, say AT5, select the VST2/3 in the top bar and select Enable MIDI Input. In AT5 you then right click on a knob and select listen and move a foot pedal.
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