I am INFJ, 53, male.
I took piano lessons for seven years starting 9th August 1990. I was a good student: 1 lesson every week for 4 years, and a double lesson every fortnight for 3 years. I practised every day, starting with 10 minutes a day, ending at 2 to 3 hours a day after 7 years' study.
I wanted to play Mozart's piano sonatas. I studied counterpoint and harmony, and played lots of Bartok's Mikrokosmos, dozens of Scarlatti sonatas from the Editio Musica Budapest edition of 200 sonatas in 4 volumes. Ah, Scarlatti! Oh, and lots of Bach. Every student of the piano gets up close and personal with the 48 preludes and fugues, and sundry other pieces, some of the Partitas, Toccatas, English and French Suites, and more besides. The piano literature is vast.
I used the study of piano technique and music as a therapeutic activity, in recovery from post-traumatic stress disorder, arising from being in a train crash. It helped.