Thanks, buddy! I managed to fix the microphone, increased the volume a few decibels here on Windows, and now it's much better to hear. You can already see that the audio is better in my second video from yesterday.
As for a webcam, I don't think I need one... I don't really like being on camera haha, so I think it's fine now. It's just a matter of adjusting the video settings so the file isn't huge and doesn't lose too much quality.