First, thanks for serving our country.
Although more costly, I think you will learn more from professional sailing instructors at a sailing school
than from an individual who although they know how to sail, probably does not know how to teach sailing very well. I had an entire course from ASA
on how to teach people sailing and there are teaching techniques including a little psychology that must be learned. Please, nobody construe what I said that I am saying an untrained instructor is incapable of teaching sailing.
The Bay Area has a number of sailing schools. Its an easy Google
search. I don't know about Monterrey.