Using a Mid 2011 iMac as an Audio Equalizer

Good morning everyone. I'm asking for advice on how to solve a problem (assuming it's a problem and that it can be solved). I have an iMac 21.5” mid 2011 High Sierra 10.13.6. If I connect an Audio/USB interface (Bheringer UMC 202 HD) via USB cable and in the audio settings I indicate it as an input and output device, the audio signal that I send enters regularly (I can record it for example with a DAW) but it does not come out in real time. In the interface I have a button that allows me to select the direct signal and the return signal via USB cable. If I select the latter, nothing can be heard. The output signal via USB is there because if I record a song I can listen to it again without problems via the interface. What is missing is an output signal in real time. Is there a way to obtain an output of the audio stream in real time? I ask because I would be interested in using the iMac as an audio equalizer and I would need the audio stream that I send via the interface to come back, always via the interface, once equalized. Is it possible? If it is possible, with what method setting and with which application? This is also a problem because the few equalizer applications that I found in the Apple Store only work with audio streams that come from the Mac itself (already recorded songs, audio from YouTube, etc.) but not with those that come from an external device (in this case the interface). Thank you very much for every valuable contribution.