iPhones have an accessibility lock. Just go to settings, accessibility, guided access.
Thank you but I don't have an iPhone. I checked the settings on my android phone but can't see anything in there and Google wasn't very helpful so far đ
You can lock the screen on YouTube
On iphone you can lock your screen to a single app maybe google and see if you can do that. If not netflix and disney plus both have an option to lock the video onto the screen as long as the app is open