Duel Masters duel played, I think, by the rules. Might help you learn the game.
Duel Masters is a great game. I play it with my son a lot and we don't get sick of it and after about 6 years we're still learning. I have a LOT of Duel masters cards since it made sense to buy around 1,000 rather than keep driving to but packs of 10 for £3 from the shops 40 minutes away. I hope this helps. There do seem to be a lot of videos of duels on youtube where either everything is happening too quickly to know what's going on or the people haven't a clue how the game is played.
Before you can summon a creature or a spell, you must build "mana". If, for example on your first turn, you have a creature or spell (not much point playing spells unless your opponent has any creatures in the battle zone for it to influence) that needs 1 mana to summon is, play the least useful card in your deck as "mana" and summon the creature. If the only creatures or spells you have in your hand need more than 1 mana, you simply put down 1 card as mana and end your turn. Each turn, you build up mana, one card at a time, and on your next turn you can play a card with 2 mana perhaps or even more if you have a specialised mana building deck. You'll get the hang of it. Play some duels and work it out. After 6 turns you should have 6 mana and most of your cards should have been playable for a few turns. Good luck.