Your 220 A/C outlet has to be the only outlet/box on the ciruit. If you’re sharing the 220 line with something else, you’re going to have to rewire it your new 110 line. Assuming the 220 A/C outlet is the only thing on the circuit, if it was me, I’d switch out the breaker. I don’t think,know if the 220 breaker is going to work properly if you have 110 outlet. Then you fold back one of the hots at the breaker and at the outlet. That will leave you with a hot, neutral and ground. It will probably be 10 gauge but that will work for 110.