1994 Saturn SL2 Odometer and gas gage dont work

Your odometer most likely doesn't work because the gear that run's it broke really common for that year and model you would have to remove the cluster and and order the gear and take the cluster apart and replace the gear or send it in to fix.The gear is like 30 or sending it in is like 130 to get it fixed.As far as your gas gauge what is it doing?

The gas gage doesn't read at all. so I never know how much gas I have

Alright for your gas gauge inside your trunk on the driver side under the vertical carpet you will find a connector under there.Move your drivers seat so you can see the gas gauge thru the back window now unplug the connector in the trunk.Turn the key to the run position engine off and jump the terminal's on the connector side that are going back inside the car.I think those would be the male terminal's.But check and make sure i'm right.Jump the purple and the black and white wire terminal's together while watching the fuel gauge if the gauge move's then i would be looking at the fuel sending unit in the gas tank.It will take a little while for the gauge to move it won't move instantly.