Poker it ain’t that hard at low middle levels, it is a matter of practice and you start seeing with your minds eye the card matrix over the head of your opponent expanding and shrinking depending on his actions and board structure.
And when he does something which is incongruent with the matrix you have, most of the time, you punish him.
Then on high level it’s very much Game Theory Based and Range Reading get more and more difficult as the game converges towards perfect balance and unexploitability