Not all phones allow you to root, even if you paid outright for the device. Termux is different from a custom ROM, Termux gives you things like native nodejs, p

Not all phones allow you to root, even if you paid outright for the device. Termux is different from a custom ROM, Termux gives you things like native nodejs, python, ffmpeg, git, and nmap. It's independent from the underlying OS. All phone come with a bootloader lock and only some companies allow you to unlock it. You need to do a bootloader and oem unlock in order to have the ability to root. Certain devices have sensors/parts that aren't supported via AOSP, back in the day I remember reading "not working: wifi" in the feature list for custom roms. I think wifi is usually okay now, but camera and cellular modem are still not guaranteed.