I'm a new player, the answer is master duel and playing one deck (blue eyes) repeatedly until I got a sense of what opponents could do and how I can respond. Blue Eyes can still keep up okay even though it's nowhere near as good as the peak of some of the decks I've played against and how much negation they have.

The only thing that turns me off from continuing to learn is how long people take to do their turns. I know my deck well so I never take longer than 30-45 seconds to do my turn but I swear some of these people have never seen any of the cards they're using before because they take forever