First time doing digital art and I finished my first manipulation. I believe I did the crediting right but if not please tell me. I also don't know how to resize it to be a horse avatar without taking the quality away.

Great work! If your asking about price I'd say 10-20k to start. But with more practice the better your art will become so you could charge more. One tip I do have for you though is to use a smaller brush when making the mane and tail. Having smaller individual strands will help your art look more realistic

For resizing you can usually change the size of the image in the same program you used draw it, depending on your program. If not looking up an image resizing/shrinking website usually works. You just download the new shrunken image and use that new one to give to HEE:)

Thank you!