I am brand new to OBS Studio, having just finished with settings and trying to record guitar lessons on my screen. I have a Macbook Pro. I need help with a couple of issues:
1. Is there a way of starting a recording of a screen video w/o starting the video, then switching over to OBS to start and top it?
2. When I try to replay the recorded video through the saved recordings of OBS, which are saved on my hard drive, it plays but the replay video is not scaled correctly and I don't get full screen coverage; the recording cuts off a lot of the original video. Plus, the recording moves around like it is in the OBS window that moves around.

What am I not getting correctly?

Thanks
Raymo