Simply put, chords generally extend from these three groups of notes: 1 3 5/ 1 4 6/7 2 5/. There are three common groups of 4/4 beat songs and chords: 1535/ 1646/7525/.
Slow-paced music can't be written for you one by one. Give you basic chords. 15135/26246/37357/41461/52572/63613/74724/.Look carefully. 1 matches the chord of 1. 2 can match the chords of 2 and 5. 3 chords that match 1 6 is a chord corresponding to 4. But you don't deserve it if you don't know it. It's complicated You'd better find someone with professional knowledge in this field to teach you. I think music theory is very complicated ... Hehe ... I can only say so much. I want to know the details.