Blackjack can be beaten with two skills. Neither needs talent, only repetition.
Strategy. For every hand against every dealer card there is one best play. Learn the chart, then drill it until you never miss. This alone brings the house edge down to about half a percent.
Counting. Keep a running total of the high and low cards that have left the shoe, turn it into a true count, and you know when the remaining cards favour you. Work down the drills in order: card values, running count, true count, index plays, a full table, and finally a bankroll session, where you size your bets from the count and see what the skill is worth in money.
Each drill has three modes: Study shows you the answers, Practice quizzes you and brings your misses back, and Test is a timed run with your best score saved in this browser.