https://www.musical-u.com/learn/how-do-you-play-a-song-by-ear/
You can learn to play songs by ear without needing a teacher or expensive materials. You don’t need the sheet music and you don’t need any special musical “gift” either.
Musical-U gives you a basic process to choose a song, and try to work it out piece by piece.
https://www.musical-u.com/learn/how-do-you-play-a-song-by-ear/