Sorry, you didn't provide enough detail for anyone to really help
-you should have noticed the pinned post in this forum, about posting a log so we can review settings and advise
More importantly though, my personal recommendation is to start simple, then go from there. So how are you connecting camera output to the computer? Are you using the Canon USB webcam utility? if so, go read Canon's FAQ/ directions, and note the video quality supported. Do you have good video quality from the camera straight into Zoom? if not fix that first, as your issue has nothing to do with OBS
As for NDI, why mention that? are you doing NDI out from OBS to Zoom? Have you looked into VirtualCam with OBS Studio v26?
