You should look into the GrapheneOS installation process. It's actually pretty easy, you can flash it from the web browser. I had a slight problem during install, so I hopped into their matrix room and someone said "try a different cable" and it worked, simple as. The process was pretty well documented, other than my bad cable all I had to do was follow the prompts, and the good cable was the one that came with the pixel, so just use that and you're gold, you can even flash it from a different android phone's browser instead of a PC, they really couldn't make it any easier.