Know the terms straight flush, four-of-a-kind (or quads), full house (or boat), flush, straight, three-of-a-kind, two-pair, pair, high card know preflop, postflop, flop, turn, river.
Obviously, you should know the ranking of the poker hands, and how cards are dealt in texas hold’em. Study Materials Good to Know Before MIT 15.S50 Begins Poker / Texas Hold’em Rules