I can make up nice melodies and think about what chords would fit that and perhaps imagine it but i cant write it down on sheet music or play it on guitar/piano. I can play the melody that comes to my mind but i cant make up the chords well. And cant know which chords would go after another. This also happens when im improvising. Im done with minor pentatonic and major scales. I wanna include some nice harmony in that. How can i learn to do that?
i think it's time for you to figure out the chords for all your favorite songs (you have to do it yourself, because you can't trust anyone else to get it right, and also this won't work anyway unless you do it yourself). the more songs you learn, the more easy the whole thing will get. i think you will find that your melodies already have obvious chords attached. it's kind of like seeing the head of an animal and knowing what kind of animal the rest of the animal would be. this gets much easier once you've seen a few animals in your day