I have a Xiaomi Redmi Note 8 Pro and it doesn't seem to support ARCore. I found some ways to dodge this but it appears to be quite complicated nor very safe. My question is: What other tools would you recommend if I want to create an app in Unity that also needs to use GPS modules, maybe altimeter and of course camera (AR stuff)? I heard about Vuforia that might do the trick, also read something about AR Foundation from Unity. But to me, it looked like depending on chosen deployment it use AR Core or AR Kit(even Vuforia). Any clearance about this maybe?
I suggest you don't try messing with your device. It doesn't support ARCore for good reason. And maybe you just try to use Android Studio Emulator, but Alas for some unknown reason, i try it but APK which is generated from unity can't be installed on the Emulator. Some stuff with the architecture
If you want to use Unity anyway. I suggest you use Vuforia. It works on most modern devices and doesn't even need device to test, just hit unity play mode and you can test around from your PC (need webcam).
Vuforia Engine provides a simulator mode in the Game view that you can activate by pressing the Play button. You can use this feature to evaluate and rapidly prototype your scene(s) without having to deploy to a device. (Source: https://library.vuforia.com/articles/Training/getting-started-with-vuforia-in-unity.html)
For Unity with ARFoundation, you can't use your PC like Unity with Vuforia, you need ARCore/ARKit supported devices.
Last if you want AR with GPS Modules (although this is not with unity) checkout AR.js https://github.com/AR-js-org/AR.js