That looks like a panasonic G85 (or possibly G7), either way they are very similiar. Both are great for photo and video. I have a G85 and it's great. That's extremely nice of your friend to give you that, especially with all the lenses. You got a crazy deal.
Where to start? First if you completely new to photography look into the basics of the exposure triangle (aperture, ISO and shutter speed). A tutorial like this https://www.youtube.com/watch?v=6_B8pVoANyY
Once you're done that I'd recommend a tutorial on your specific camera, to get to know it's ins and outs. This one is really good for the G85 (he uses a G95 but it's basically the same) https://www.youtube.com/watch?v=S3bt0zLR4zY
. Even though it's 2 hours long I'd highly recommend watching the whole thing, you'll learn a lot.
After that just start shooting, the more you shoot the better you'll get. But like everything it comes with time.
Once you're comfortable with the camera and taking pictures, I'd recommend downloading a raw image editor. I recommend darktable as it's free. Then look up some tutorials on that.