Will I have cell service in Mexico?
What plan do you have on your account? You should be able to log in to My Verizon and check if you have an international plan or if your plan includes Canada and Mexico.
All the current service plans include Mexico when your phone is on roaming. However, if you've got something very old, I've heard plans from way, way back do not necessarily have any international coverage whatsoever. Otherwise, if you are postpaid, you'd simply need to enable roaming when in Mexico and you'd get a text saying TravelPass has activated.
If you are prepaid, before you leave the US, ensure the TravelPass toggle is turned on in your account and that you've loaded funds sufficient to cover the number of TravelPass days you want into your account. Otherwise, a prepaid line does not work at all outside the US. For Mexico, I want to say TravelPass is $6/day.