Hello and welcome.
I personally haven't used Teams, as we use Google Meet at my work. I do know that all video conferencing platforms have intermittent issues, due to the entire world using them during this trying time.
That said:
-Which exact model Mac?
-Which version of macOS Catalina?
-Which version of Microsoft Office/Teams?
-Does it crash intermittently, a lot, when launching, etc.?
-Was it working fine, then the issue started - possibly after a macOS or Microsoft update?
C