The Wizard explains the rules and strategy to blackjack on his demo game: https://wizardofodds.com/play/blackjack/
Everything you need to know about BJ21, the rules, strategy guide, odds, video tutorials and more at: https://wizardofodds.com/games/blackjack/
21+ Play responsibly – Gambling help :
http://www.gamcare.org.uk/ and https://www.begambleaware.org/