The ability to run when choked maybe indicative of two potential problems: weak spark,an improperly adjusted or dirty carburetor, or an induction system air leak that leans the mixture.
While fuel delivery could be an issue, it usually does not respond to choking. Nonetheless it's easy to check as John(UK) pointed out.Check the spark first by removing the center lead from the distributor cap, holding it near a good ground, turning on the ignition switch and trying a start. You should see a FAT, BLUISH-WHITE SPARK FROM THE HIGH TENSION LEAD. If you don't the problem is most likely in the primary ignition circuit(dirty or corroded points , improper point gap, bad primary connections, worn key switch, etc.) A weak spark will more easily ignite a richer mixture.
If you have the requiste FAT, BLUISH-WHITE SPARK, then the problem most likely is caused by an overly lean mixture that can be caused by improper carb adjustment, dirty carb or leaky induction system. Adust the idle mixture screw by turning it in gently til it stops and turning it out about 3/4 turns. Adjust the power jet(big screw) again turning it in gently and then out 1-1/4 turns. Now try a start and see how that works. If you still have problems, get some starting fluid and get the engine started and running. You may have to have someone help you keep it running while you CAREFULLY spray the starting fluid around the throttle shaft on the outside of the carb, the joint between the carb and the intake manifold and the manifold to cylinder head joint. A leak will suck the starting fluid in and a momentary speed increase will result. The point where that happens is where the leak is at. If all these tests don't point to the problem area, you'll have to remove the carb , soak it inreal carb cleanerfor a day or two, blow out all the passages with compressed air and replace the gaskets.
Do all these checks syematically, check to see if each potential fix corrected the problem before moving to the the next step. Write the results down for future reference. Doing it systematically helps you learn and gets to the root cause of the problem.
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