You will almost certainly end up with 2 or maybe even 3 kites.
IMO best to go with a large kite for your weight to start with.
Learn in lighter winds with a slower kite. WTG

When skills & confidence builds then look for a smaller kite for the windier days.
At 55kg 8M or 9M would be the go BUT keep it to light wind days only.
Dont ever discount the value of a body drag session - as long as you are moving under your kite you are learning kite skills.
Esp as a raw recruit when you are body dragging you can concentrate solely on the kite - kite skills are 90%+ of the game.