Get a capture card to go between the computer and the camcorder. Put a tape in the camcorder. Set up OBS for a reasonable frame size given the video format (NTSC / PAL / SECAM are not worth a 4k frame), and everything else while you're at it. Then create a scene that uses the capture card.
If the capture card also includes audio, you're good to go. If not, get a Behringer UCA202 as well. That's the cheapest stereo line input that I know of that works well. Using that will prevent you from plugging the camcorder's line out into the computer's mic in + power, which are not compatible with each other.
You may also need to set up OBS to use the correct audio input, whatever it ends up being, and route it to your speakers.
To view, push play on the camcorder.
To record, also click record in OBS.
