To move the pieces, click on a piece and drag it to where you want it.
Turn your sound on, because when you put 2 correct pieces together, it will make a clicking sound.
If you want to do an easier/harder puzzle, click Shapes on the left bar and select a different number. When you finish the puzzle, click Shuffle on the left to redo the puzzle. If you can't figure out the puzzle, click Solve on the left bar.