Translation:Which is it?
I put "Which way is it" and got marked wrong; told to put "Which 1 is it"
It probably said that because it wanted you to put "Which one is it?", but since 1 can be written out as one, both can be accepted. At least, that has been what I've been noticing even in other courses.
どっち refers to direction, no? "Which is it" would be どれですか？ Reported.
どれ is "which" when you have three or more choices.
どっち and どちら are "which" when you have only two choices.
どっち•どちら can also mean where or which way.
どっちに行く。Which way are you going?
どちらからですか。Where are you from?
In addition to B_bethany's explanation, I would mention that どちら is more polite than どっち. どちら would actually be considered the regular form. Unless you are on familiar terms with the other party and they speak casually with you, it is probably best to stick to どちら until you're more comfortable.
どちら can also mean 'who', as in 'Who are you' / 'Who is calling?' どちら様（さま）でしょうか？
god ❤❤❤❤❤❤... which way was marked wrong -_- this app really has to go a long way still