I wrote a simple guide for this back at the start of Covid 2020, but to be honest you're probably best following some better packaged YouTube tutorial these days.

Our set up:

• OBS Studio
• Elgato Stream Deck
• Panasonic GH5
• Elgato HD 60S+ (*see below note)
• YouTube

Notes

• The Stream Deck has been GREAT to simplify training for our AV team volunteers.
• The computer mobo has USB ports connected to either the APU or Southbridge's upstream USB host controller (read the motherboard's manual). We found that the capture card must be connected to whichever on its own. All other USB devices should be on the other USB host controller OR else we get intermittent capture card device disconnects/freezes. I think it's because the 4K video data requires heaps of bandwidth…
• Unfortunately we can't programmatically automate the camera's zoom (easily). So we instead capture the video at 4K but then use OBS scenes with different crops.

1. Reboot PC
2. Try a different port
3. Any recent software version upgrades? May be due to incompatibilities.