What’s the best/healthiest thing to order at a Mexican restaurant?

So I have to go out to eat at a Mexican restaurant;
I doubt they’ll have nutrition charts available at the restaurant since it’s a local business and not a chain restaurant.
What should I order ? What will have the least amount of calories?
Suggest something that pretty much any Mexican restaurant has thanks !

Get two fish tacos without dressing in them. Ask for fresh salsa or tamatio instead. No refried beans!