It may depend on the type of vehicle you own, but there is probably only one container. If the tank was empty, the line may need a few tries to fill up - the fluid has to go from the front of the car to the back. also, check to make sure the sprayer is not clogged by any surface dirt/ice.
You most likely have a van or SUV. Open the rear hatch and look on the side pillars for something that looks like a place to pour fluid in. That will be for your rear washer. If not on the pillar, open the side storage panels. It may be in there.
Check owners manual. If only 1 container your rear washer motor may be out. (Usually on container)
Just because YOU know what you drive doesn't mean WE do. If you would have told us what it is, we could've given you an exact answer to your question complete with where and how to fill if there is more than one.
Type of vehicle????? Station wagons SOMETIMES have 2 but all others USUALLY only 1. Without DETAILS it is all guess work though.
It is one in the same.
My light is on for the windshield washer reserve. I have filled the container under the hood but is there a container to fill the rear window