What's wrong with a '73 Buick Century that won't run but turns over and fires a bit whn gas is poured in carb?

Im 16 years old and wanting to buy a 1973 Buick Century. It's been sitting for 4 years in a garage and it was parked because it stalled one day when the lady who drove it, Didn't let it warm up. She took off one day and a couple miles later it stalled and it hasn't been started since. It fires but does not run when gas is put into the Carb. From the sound of it fire-ing, im sure its hitting all cylinders. and im pretty sure theres spark. any help?