Basically I tried different tutorials for changing the resolution but nothing changes. I’m the trying to set it to 640x480 fullscreen with two black bars.
maybe it works with appropriate device. So you would like to test at the right device which has 640 x 480 resolution.You can’t test it 1920 x 1080 kinds of general desktop.
Or try this logic.
First, Add config files in your root directory.