Help with my carburetor problem?

Even if you messed with these screws, the thing should start if you squirt some gas in the carb. I would take the spark plugs out and see what condition they are. They should not be wet, dark, or glazed. The preferred state is a light tan flat color. You may need to replace the plugs or if you can get to a sand blaster, clean them so they look white. The spark gap should be about 3/32". With this done, try again to start the car. If it still will not start, squirt some gas into the carb and try to start. If this does not work, take the plugs out again and turn the engine over a few times. Squirt a little gas in each cylinder, put the plugs back in and try again. If you get it running and it doesn't want to stay running, turn up the idle and adjust the idle jet screw (I usually turn it all the way in and back it out about 2 turns).