Set the camera to HD (also called 1080p) this is good enough for almost anything... YouTube etc
Get some sort of cheap tripod for the camera and two lights....cheap flat panel LEDs....panels should be 8" or 10" square...and some way of mounting the LED panels
Make sure you speak loudly enough and keep you voice volume consistent.
You can get an inexpensive mic that clips onto your shirt and plugs into the camera...they are called Lavaliere mics. That makes your audio much better...but the built in mic on the GoPro works ok....just make sure you speak up.
Make or get a clap board (anything that you can easily see in the frame of your shot and makes a noise...just like Hollywood uses) use it before each segment you film...it will save you alot of time in editing...alot of time.
There are several free video editing software programs...just Google up free video editing software.
Make a few 30 second test videos...rinse lather repeat.
Good luck !