Is your OBS freezing when you try and select a video capture device (camera icon)? If so: the error is probably with an nvidia driver update last October. The only fix I know of for that bug is rolling back to the earlier driver, which I don't recommend. I've been away from the Vtuber software stuff for some time, so this feature may be available in VNyan or VSeeFace, as well it can be done using some tricks in OBS. Here's the old guide from Graves: https://twitter.com/Virtual_Graves/status/1434154401707397120