Fixing the idle screws is one thing, but you need to clean the jets also, carb medic will help dissolve the residue left by old/bad gas. it is Not really voodoo. Dont expect it to make bad gas good again though, unless you like replacing push rods on stuck valves or worse.
OP says he can two foot it to keep it running, car can run on the main jets if that is the case; most likely the culprit is some kind of minor obstruction in the idle circuit.
In the past 15 years I haven’t seen any kind of carb goop that works, the good stuff seems to be off the market, if a carb is gunked up bad enough to be getting some kind of mechanic in a can poured in it, it’s bad enough to get an actual cleaning.