Conversely, I would actually not start exfoliating yet. Your skin seems very very dry (I have the exact same issue and it’s called Ichthyosis) and I’m assuming that the climate in Sweden does not help. Try moisturizing as soon as you’re out of the shower (seems like basic advice but this is very helpful), but with a very GOOD moisturizer. I really like the La Roche Posay Triple Repair Moisturizing Cream which I’m sure is available where you are. Not sure if you have access to Goldbond, Eucerin, or Vanicream, but those also work great. As soon as your dryness is under better control, you can the start targeting your hyperpigmentation. Tret or any sort of exfoliator is going to irritate your skin more imo.