Interfacing with musical instruments

I'm using Zoom 6.0.11 on my Macbook Air with an M2 chip. The OS is Sonoma 14.4.1. 

Also, I use a  Behringer UM1820 digital interface for sound. When using the microphone through the digital interface during a meeting the  others can hear me. However when I plug in a musical intrument, it can't be heard. How can the musical intrument as well as my voice when using the digital interface?