Toyota Sienna 2000 Model

Few days ago, I started hearing the sound
of the engine louder than usual and as of
now the car drives like it's dragging a
heavy load. When I engage the gear in
reverse, it makes a hard sound and double
shift sound as if about drive with the
handbrake on and when I move to the
drive mode the sound is once. Just this
morning, my check engine light came on.
What can I do?