@bunchy7s Note that the Oneplus 3 port isn't even listed on the main devices page. The page @moem dug up says that the last work on it was in 2021 and is for UT 16.04, which is quite out of date. And the video you followed is four years old.
I can't say that your issues are definitely caused by how out of date it is, but I can say that you're unlikely to have a good experience of Ubuntu Touch on that device.
Unless you want to take up the reins and bring the Oneplus 3 port up to date, I'd say your best bet to try UT is to read around on the forum and device pages and try to find a supported device that suits your needs and is affordable and available in your area.
Also of note: some people have difficulty with putting a phone back to android, so do your homework on that before attempting.. people have bricked their devices.