First of all, you have to select your main microphone at Voicemod. Afterward, select the Voicemeeter Auxilliary Input as your Output device within Voicemod. This Auxilliary Input will allow us to separate the Voicemod monitoring from your system sounds.
Then, to control your outputs through Voicemeeter, you have to select the Voicemeeter Input device as your preferred default Output device for Windows.
Then, make sure that Voicemeeter is set as follows; where the Hardware Input 1 is dedicated to your Microphone, Hardware Input 2 for the Voicemod Microphone and Hardware Output (A1) device for your headsets/headphones.
After that, to listen/monitor the inputs you want you enable A1 and to stream the inputs you want you enable B1.
Lastly, to stream all these inputs (B1), you will have to activate Voicemeeter Output in your OBS.