As you play the game levels will go up, but you need to start at a low level to help you practice.
Try to move the tetrominoes to get them to move together.
In traditional tetrix games there are seven different types of tetrominoes:
I-blocks are useful for getting competing four lines at once.
O-blocks for filling large gaps.
L-blocks for filling medium-sized holes.
J-blocks face the opposite direction as L-blocks.
S-blocks for filling small holes.
Z-blocks face the opposite direction as S-blocks.
T-blocks are also for filling small holes.
The more lines completed at once, the more points gained.
Check upcoming pieces and plan for them. This will become easier the more you play, don't rush yourself.