2000 Chevrolet Monte Carlo takes several tries to start

Car starts after pumping gas approximately 10 times.

Pumping the gas pedal is only exercising your leg. This car is fuel injected.

I suspect the fuel pump’s anti-backflow valve has failed and maybe the pump is close behind. Try truning the key ON, but not start, back OFF. Repeat this 3-4 times listening for the hum of the fuel pump under the rear seat. Then try and start the car. If it starts right up it it is the anti-backflow valve. Have the fuel pressure checked as well as the fuel pressure regulator.