"Are you going?"
"Вы идё́те" can be used for both - at some time in the future (as in Future Simple in English), or now (as in Present Continuous in English). Examples:
Вы идёте на концерт завтра вечером? - Do (/will) you go to the concert tomorrow evening?
(When you are calling smb by phone) Ты идёшь по улице? - Are you walking down the street?
"Ты пойдё́шь" Is used for future only. Exampe:
Сейчас начинается интересное ТВ шоу, пойдешь смотреть его? - Now is beginning an interesting TV show, do (/will) you go to watch it?
For Future Tense these both can be used interchangeably:
"Вы идёте на концерт?" and "вы пойдёте на концерт?" are the same.
"Ты пойдёшь смотреть шоу?" and "ты идёшь смотреть шоу" are the same.
"Ходишь" is a multidirectional verb of motion, it doesn't fit here. If you say "ты ходишь?" it would sound as if you were asking whether that person is capable of walking in general, but even then it sounds a bit strange. It may be an incredulous "You are walking?!" when someone whom you've previously only seen in a wheelchair is suddenly on their feet.
That's the meaning I would have for "Are you going?" 'Are you going/' is something I might use in special circumstances, but "Are you leaving?" is what I would normally use when someone is or is not departing -- and that's what thought the Russian is about. If not, what does the Russian mean?
If you are familiar with a person and don't really need to be too formal with him (like familiy, friends or because you are a person speaking generally informal in a friendly way) that is totally fine. But to people you don't know or with buissness partners you should talk formally. That is how Duolingo teaches you mostly and you should learn a language first that way. Hope that helps.
This has been discussed in a couple of other posts and, apparently, there's a helpful explanation on stackexchange. I don't know the details, but I have noted Don't remove the personal pronoun in Russian (ie you can in certain exceptional situations, but why bother figure those out at our level, since keeping the pronoun is never wrong).
Hmm, we need to use "ë" in this verb, rather than just "e".
Apparently, Russian verbs are divided into 3 categories: Conjugation 1a (e-verbs), Conjugation 1b (ё-verbs) and Conjugation 2 (и-verbs).
Examples of verbs: In 1a. Знать, Читать; in 1b. Петь, Звать; in 2. Говорить, Готовить (https://www.ielanguages.com/russian2.html).
1st question: if my verb's infinitive ends in "a", how do I know if it belongs in category 1a or 1b?
2nd question: how do I do I find a verb's infinitive? (I looked up идёшь on Wiktionary and found a link to its impf. form идти́; on that page I discovered the "derived term" ходи́ть which I supposed was the infinitive. But that can't be, cos then идёшь would belong in Category 2, rather than in 1b where it clearly belongs due to the ending with "ë"...)
Answers: "verbs ending in -ать are usually 1st Conjugation, and verbs ending in -ить are usually 2nd Conjugation. Verbs ending in -еть can be either, and verbs ending in -сти are almost always 1b, though their stems tend to be irregular. The easiest way to find out for sure is when you look up a verb in your dictionary, look at the ты or он form, and look to see which vowel is used; the same series of endings are always used otherwise, the rest is easy." (ielanguages)