>  Lesson 1 – Get to know the notes on a piano
Lesson 2 – Basic scale theory
Lesson 3 – Basic chord structures
Lesson 4 – Learn to play two songs
Lesson 5 – Practice your ear
Lesson 6 – Notes and fingering
Lesson 7 – Add melody to chords
Lesson 8 – Understanding and expanding chords
Lesson 9 – Harmonic principles and progressions

The best way to learn is to learn with your left and right brain.  Try also to see where the notes are in pictures (e.g. an F is just left of any group of three black notes):

Each descending or ascending note on a piano is a semitone (half tone) higher or lower than the previous note.

A sharp  is normally a black note and is a semitone higher than the plain white note (e.g. C^#).

A flat is also normally a black note and is a semitone lower than the plain white note (e.g. D^b).

On a piano, a C^# and a D^b is therefore the same note.

Take time to understand this...

Depending on which key you are in, you either use flats or sharps (e.g. you use sharps in the key of D, E, etc. and you use flats in F).  To understand this, you need to understand basic scale theory.

Advance to Lesson 2.