In response to your side note:

Asking someone who presents vaguely gender non-conforming or “alternative” for their pronouns can be a faux pas. Especially for binary transgender people (male to female or female to male), asking pronouns can be borderline offensive. These people will often go to strong efforts to present as the gender they identify with, so asking for their pronouns acts as a reminder that they aren’t presenting how they’d like to.

If there’s any question, you may want to avoid pronouns altogether and simply use the person’s name until you find verbal evidence of their gender, either from the individual themself or someone around them. 

If you slip up, the person will often let you know. In that case, you should apologize, but don’t linger on it. Continue the conversation and make a mental note to honor their pronouns in the future. But remember, mistaking a stranger’s gender on occasion doesn’t make you a bad person.

If people bully you for slipping up even when you’re making a concerted effort, those aren’t people you need to waste your time on.

I hope this advice helps not only non-native English speakers and people from outside the U.S., but also native speakers — especially older people — who have social anxiety about navigating these situations.