My potiac grand prix won't move in D but will move in R

For a while, my car would do a big jerk when I accelerate from a stop. (
Gussing it have to do with changing gears ) One day I noticed it got a lot
worst and completely stopped driving in the Drive gear. It started to only rev
without going anywhere. I reversed the car into a parking lot but luckily I was
just down the street from my house so I wanted to attempt to make it home.
When slightly pressing the gas it started to move again so I was able to get
home but I can't really drive it no more. I checked the transmission fluid and
it seemed like it was almost none in it so today I just put some in but not sure
if I would have to let the car sit or run for a while for it to take a affect.