How should I pronounce ACoA - the acronym standing for Adult Children of Alcoholics?
When you say an acronym you should spell out each letter individually.
The only exception to that is when the acronym is well-known enough that there can be no confusion, for example NATO, FIFA or CERN, or when there is an accepted pronunciation (such as "Fannie Mae" for FNMA) or when the initialism forms an already-accepted word.
Some organizations like to decide on the pronunciation of their acronym, and it may be that ACoA has a preferred pronunciation, in which case you should follow that. But if you see an unfamiliar acronym written out, and have to pronounce it, just say the letters.
One possibility is ah-ko-ah, but clarity of meaning is key here. If there's a standard usage, then I would suggest following it; I also imagine, however, that some people whose parents were alcoholic might resent being "reduced to a label".