The first is to adapt the original music into fingering music, that is, to use a guitar with both accompaniment and main melody. If you need this kind of music, just wait. Most people can't adapt it.

The second case is to calculate the accompaniment chords only according to the main melody melody of the original score, and play and sing. In this case, it is simple to learn the root sounds of chords first, then learn the rhythm and beat, and finally match each bar with corresponding chords. Some bars can be matched with two or three. If you want to match them perfectly, you need to have very solid basic musical theory skills and excellent guitar skills.