Actually GO SKATE! Stop fluffing around getting all your ducks in a row, and just hit up some public sessions regularly. Don't worry about lessons too much, you need time on skates.
The best exercise for skating is .... skating ...
Find some public sessions, and just skate. LOTS. Eventually it'll became clear which specific muscles you're particularly weak on, but for now you're probably weak on ALL of them. Though hamstrings and glutes will be the most useful ones to build up first.
Nutritional tips: You state somewhere else that you suffer from anxiety. You may be short in magnesium (and lots of people are). Magnesium deficiency makes a feeling like living in a war zone. If you skate lots, you may need more iron too, as exercise rapidly turns over red blood cells. And lots of protein. Can't build muscles without protein. Zinc too maybe (foot ezcema is a dead giveaway for a deficiency).