I can't stand cilantro, but I like Mexican food. What can be susubstituted?

Culantro and cilantro are the same thing, just depends where in Latin America you are.

Sorry, Fran. They are distantly related but are not the same. See:

https://www.thespruceeats.com/is-culantro-the-same-as-cilantro-1807011

The problem strives in how those two herbs are called in different countries. https://en.wikipedia.org/wiki/Coriander
and https://en.wikipedia.org/wiki/Eryngium_foetidum

By coriander do you mean the seeds?
If you like them, yrs they give a nice, mildly spicy and somewhat citrus flavor. Either warm them whole in oil used for frying (and remove before serving), or add ground to sauce.

Coriander and cilantro are the same plant. Coriander is the name used for the seeds. Cilantro is the name used for the leaves.

You have multiple options here. You can replace the cilantro with another herb from the same family (chervil, parsley). You could replace it with another common used Mexican herb that is unrelated to cilantro (like Mexican oregano or epazote). Or you could simply use some completely unrelated Old World herb that you like such as thyme or marjoram.

Note that there are various types of oregano. Origanum is a Old World genus. This covers many oreganos as well marjoram. "Mexican oregano" is an unrelated plant that is widely used in Mexican cuisine.

Ultimately you should just use what will please the diners at your table.

702551, Thanks! I did know that coriander & cilantro are from the same plant (go figure.) But, I did not know about chervil and parsley being in the same family. I also didn't know about different types of oregano. What is epazote?

"Epazote is, in my opinion, the most Mexican of the culinary herbs... It is the sine qua non for the cooking of black beans, for tortilla and other brothy soups, in quesadillas, chopped with fresh corn, and elsewhere." -Diana Kennedy (The Essential Cuisines of Mexico, p. 486)

I'll leave it as an exercise for you to read more about this on the Internet. There's no need for me to regurgitate what's on Wikipedia. I'm sure Rick Bayless has written volumes on epazote.

Seeds are not difficult to find online and many nurseries on the West Coast have epazote.

This perennial is rather invasive so have you have successfully grown it, it will tend to spread. It is not a fussy crop and thrives with very little maintenance.