game controllers - Can I use USB gamepad without any setup?

I connected USB gamepad to my tablet.

I noticed that software like Tincore KeyMapper requires root access to connect to this gamepad. This type of software recognizes all buttons, but asks me to map these buttons to screen areas.

1. Can I use a gamepad without mapping buttons to screen?


2. Do games support this mode?



3. Do I need to download some piece of software that will ask root access for these games?