There are many areas in Mexico where one does not have to speak Spanish at all to live quite comfortably. Other, less traveled parts of Mexico, speak very little English. Do your research ahead of time.
Of course, itâ€™s always good to learn what you can, and many retirees enjoy taking advantage of affordable and informal lessons offered by locals enthusiastic to welcome others into their culture. Take advantage of local libraries that may have access to online language courses, or buy your own if needed.
Remember, you are leaving your home and visiting another's home. The polite and reasonable thing to do is to learn enough of the language to show respect for the country you're in. You want visitors to your country to learn a little of your language, so it stands to reason that you would want to do the same.