https://www.musical-u.com/learn/6-simple-steps-play-by-ear-solfa/
Playing music by ear can seem mysterious. If you want to learn, wouldn’t it be great if there was actually a clear and logical process to it, rather than seeming like a magic trick?
The good news: there is!
https://www.musical-u.com/learn/6-simple-steps-play-by-ear-solfa/