"I wish to order coffee" has the same connotation as "I want to..." in english
Yes, but Duolingo wants you to translate the verb as it is. To wish is a different verb. The creators may think you don't know the vocabulary.
That would be more like "Я бажаю замовити каву". Which can be translated as "I desire to order coffee". Which could be translated as "Я прагну замовити каву". Which can be translated as "I strive to order coffee". And so on.
There are always dozens of ways to rephrase a sentence. There is no time, manpower and need to include all of them :) In this course, хочу <-> want. It's not so hard to remember, I hope :)