i'm gonna second what gypsyfish said. i'm currently in cdmx and LOVING IT, the other day i took the tren ligero (light rail) to the ancient canals in the southeast of the city, it's breathtaking and ancient and natural 💚💚💚 you will have a great time as long as you stay SMART (keep an eye on your things) while still being adventurous!! my advice: try everything and talk to everyone.
it definitely helps to know spanish, but not totally necessary. my spanish is good not great--i speak better than i understand--so to me it's actually annoying how many ppl talk to me in english when i'm trying to practice!! 😅 if you walk into an establishment, there's a good chance someone there will speak at least a little english.
i'm doing this all alone, and i haven't actually met other tourists. if you want travel buddies, just stay at one of the hostels--there are plenty. get down here, with or without yr mom, and stay as long as you can 🙂 you'll never forget it 💕🇲🇽💕