Cranks will not start and it sounds like it is sucking in air

I bought this car to fix up and re sell. Well, today I did a bunch of work to it. I changed the instrument cluster due to the gauges not working, changed the valve cover gasket, and spark plugs and coil pack. I did notice when I removed the old spark plugs that one of them was cross threaded, however the new spark plug went in fine. But now that I'm all done, when I try to start the car it will crank but not start and it sounds like it's sucking in air somewhere. Kind of stumped.