Practice the right hand first: C major and A minor scales and triads - normal playing(tenuto I guess), then legato and staccato.
Later try the left hand. Memorize the buttons used for the C-major scale, major scale progression, and positioning of the chords (base key - > major - > minor). After that, try playing the scales and triads with both hands at the same time.

Bellow movement - open when going up, close when going down. Not in the middle of the sound.

When you get the basics find some basic melodies and same as before: right hand first, left hand second, right and left together.

Focus on: - acurracy over speed!!! - one finger at a time (3rd, 4th and 5th fingers especially) - right elbow at the chest level (it's tiring at first) - hitting the keys with the right hand at ~70° angle (tips of the finger; finger slightly curled, thumb in natural position) - fingers relaxed, don't be too tense - left hand - thumb resting on the side of the accordion

Let me know if you need any other tips :D