Mexico is a great choice for travel for two. I like this country very much. Author, I would recommend you find more information on the U.Travel guide website. That's how I chose a resort for me, find out how to book flights and hotel. As for choosing a resort: here is information about what resorts are available in Tulum https://u.travel/mexico/tulum-1/tulum-hotels/top-10-adult-only-hotels-in-tulum/