In my bathroom the shower runs as well as the facet as if I were running water to take a bath. The water pressure from the shower head is no that strong. What can I do to have just the shower water running?

The spout where the water comes out for the bath has a valve on it. When you switch from bath to shower the lever that you use shuts off the water to the spout.
The spout is replaceable. On the underside there will be a screw or allan key to unscrew. Once the screw is loosened the spout should be able to be removed.
Its better to get a new one first from a hardware store and look at how its attached. This will give you a better idea of how to change it.
They are only a few dollars and it is well worth the cost to replace it.
Hope this helps