Check engine light on, running A/C makes car try to shut off.A

I guess it is, the battery is a year old, the guy said the only thing it showed was low voltage- and trouble with memory board. When A/C was on I tried to accelerate and it didn't want to go . Like it wasn't getting fuel. The turn signal dash light blinks real fast now also but they said that's because the computer memory board needs to be flashed ? Is that a normal , easy repair? Would the mass air flow system make it want to shut off and not accelerate That's about the only repair that hasn't been done. Defrost also makes it want to cut off. I just want to see if I should have it fixed or is this an expensive repair.

test batt and altenator