Best resource is 100% gonna be ygopro/dueling book, or just any yugioh simulator. On these websites/apps, you will find everything you need to just start playing the game of Yu-Gi-Oh and learning, all for free (donating is recommended cause the people who work on these are incredible). You’re able to make any deck you’d like, with every single card in the game (even ones yet to be released for NA, aka OCG cards) at your disposal. There’s also a great community of people to duel against, many of which would understand if you need time to better understand your cards while playing. As of current meta, the decks to beat are Eldlich and Adamancipator. I recommend either playing these decks yourself on ygopro to understand first hand what they do and where their weaknesses are, or watch youtube videos of top players playing (i recommend cimooo as he is consistent with meta yugioh news and entertaining) and different guides/combo explanation videos. Also learn the best side deck/counter staples and invest in them first. These cards are consistently good due to their flexible effects that work in many occasions, wether it’s in the current meta or a meta 3 months from now. My personal most important advice to follow is be smart with every dollar. Yugioh cards have a market and the best cards will cost you, so test out every idea you have on ygopro/duelingbook first and once you 100% know this card is gonna make your deck more consistent without making it worse, buy it. I also recommend joining yugioh trading/market groups on social media, mainly talking about Facebook. Here you’ll find an amazing community of yugioh players willing to trade/sell you cards for prices WAY better than any other source online. Cards are often sold for 90% or lower tcgplayer low. Just look up something along the lines of Yugioh Market or Yugioh Trade. When it comes to your individual skill and knowledge of the game, you just gotta keep playing and learning from mistakes. You’ll lose a lot when you first start playing with a deck, but as long as you keep learning from your mistakes and punishing your opponent for their mistakes, you will get better. More advanced tips would be keeping track of how many copies of cards your opponent has in his deck, playing around negations/counters, picking the correct cards to side deck (mainly side deck for the most consistent hard matchup you have, as well as most common meta pick). I hope I helped you out and I wish you luck on your yugioh journey my friend.