When I start my car it runs good but when I drive it starts to pull back and shaks and wants to turn off. Also when I'm on the freeway it started doing the same. Also the gas meter when it get between half a tank and empty it wants to turn off as if it was on empty.. can you help?

I would replace the Ignition Control Module (ICM) and coil inside the distributor. This is the ideal time to also replace the distributor cap and rotor, which often cause the ICM and coil to fail.