https://www.musical-u.com/learn/how-to-find-the-tonic-of-any-song-in-a-major-key/
One of the most important skills you can learn with ear training is how to find the tonic of a given song or composition.
This gives you information about how the music is organized, and tells you what chords it is likely rooted in.
Also, if you get lost in a song and can’t understand what’s going on musically, using the tonic as a point of reference can help get you back on track!
in this lesson we teach you how to find the tonic of any song in a Major Key!