is a covid test done by CVS Walgreens accepted at the time of traveling out to Mexico City (airline Volaris) ?

I'm sure it is but I don't think you have to have a covid to fly as far as I know . But if you have your colored vaccine you're good to go I think

Your safest option would be to contact the airline "Volaris," customer service and ask them directly about their policies regarding covid testing.

I would think so as long as it's a certified test by a legitimate company

Not sure, we traveled within USA.