>>331879643
That's it really. New people try to learn too many yaku, most of which are rare and should not be forced.

Just learn these to start:
1) basic flow of the game turn order and types of calls (chi,pon,kan,ron, tsumo), what makes a complete hand, pairs, sets(1-2-3) and runs(3-3-3), reading the dora.
2) Richii [no open calls made, waiting on last tile]
3) Tanyao [only 2-8 tiles, can have Chi, pon kan calls]
4) Pinfu [No open calls, only sequences and a pair that is not a dragon, your seat wind, or round wind. Your final wait must be 2 sided as in a run like 4,5 waiting on 3 or 6]
5) Yakuhai [ draw or call a set of dragons, your seat wind or round wind]
90% of the time your hand is some form of the above. Focus here.