SO many places to start here!!!
the typical reasons are tune up related/ignition/carb.
make sure your point and spark plugs are in good shape and adjusted properly. As well, make sure your timing is set right too. Set base at 10-15 degrees, and total at 32-36 degrees (if you have a timing gun)
however, it's most likely a carb issue as you mentioned. The very first suspect is a vacuum leak. Vacuum leaks are sometime easily detected by a hissing sound under the hood. You want to look at all the ports off the intake and carb, follow the lines, make sure they're all terminated and none of them are disconnected. You can get a vacuum guage from autozone if you're unsure for about $20....that guage simply plugs into a vacuum source at your intake. 17-20 pounds and you're good. Any less and you have a leak.
If you have no leak, your idle speed could be too low. There is an idle speed adjustment on the dr side middle of the carb. it's a screw that you turn. you want the rpms to be about 700 give or take.