I edit a video every fortnight or so and use
Power Director. It's got more features than most Go Pro users would ever use. More than enough to edit a quality video from Go Pro footage. It's a stable middle of the road editor. Costs just a bit over $100 to buy though.
Here's an edit I did recently. I've been learning slowly (mainly through trial and error) and steadily getting better at the editing process.
If you want to go free then try
DaVinci Resolve. From memory you have to plug in an email address and some details before it can be downloaded. So even through it's free expect them to daily email Spam you 'offers'.
If you can't be bothered with all that
Windows has a Video editor built in as standard. Probably the best way to go if you are just doing a simple once off edit. Bit of info about it here:
www.howtogeek.com/355524/how-to-use-windows-10s-hidden-video-editor/