How would I go about to make an account creation system like League of Legends but a online data storage system with different currencies and character progression per account like Brawlhalla. My goal is to have people make their account on my website or in game with their email, password, username and alias. Then be able to play the game once their email has been verified.
EDIT:
A third party storage system where you register on the website then log in in-game and the game occasionally sends variables (like currency and progression) to the website and then the game gets said info/variables when they log in to that account, would be just as good if not better.