Translation:I am going to have dinner at my parents' place.
Whenever you see a conjugated form of the verb "aller" and then an infinitive, then it is in the future tense. In english, we also use the verb "to go" for the future, like "I am going to sleep". Same thing with the question above, in english it translates to "I am going to dine". What you said is incorrect, because you said "I go dine", which is still in the present tense.
The Duo sentence is reasonable (the apostrophe at the end is may surprise you but it is correct), but let's break it down. "je vais" = I am going. "dîner" = to dine <or> to have dinner. (Where are you having dinner?) "Chez mes parents" = at my parents' house. The use of "je vais" with an infinitive is often translated as "I will + infinitive" so there are no surprises here.
this isn't correct, I will eat "with" my parents would be better. You better don't eat "in" your parents, don't think they'll appreciate that. Would be quite though on their body's. There are a few poorly translated sentences. Not only in this category but in "negatives" too.
I'm not sure I agree.
I admit that both the "going" structure and the "will" structure can be used to indicate futurity, and in some contexts they may be interchangeable.
However, if you ask a native English speaker, "What are you doing tonight?", 99% will answer "I'm going to have dinner at my parents' place". If they answer "I will have dinner at my parents' place", that's a pretty good sign they are foreigners speaking English as a second language.
Actually, "I am going to dinner" is correct English. It is not, however, the right answer here.
Based on the French DL gives us, your answer must include (1) a near future (am going); (2) a verb "dine" or "have dinner" or "eat dinner" rather than just a noun "dinner"; (3) recognition that both (two) parents are involved.
The French "mes parents" is both plural and possessive. In English, this requires an apostrophe after the "s": parents'. If Duo doesn't accept "I am going to dinner at my parents'", then I would report it again.
Duo normally ignores most punctuation, but in these possessive exercises, it does insist on the apostrophe being in the right place.
UPDATE: Based on @ion1122's comment below, I agree with him that this sentence needs a verb "to dine" / "to have dinner" vs. the noun "dinner", at least if one is being picky about having the same the same general structure as the French.
I agree. I realized that I probably should have added the apostrophe after I reported it, but I was just focusing on the sentence in general. We'll see how Duo rules. Maybe they'll add the apostrophe, but at least they should accept that translation. It was the most natural to me.
rain-on-roof, another possible "problem" with your translation is that French uses the verb "dîner" whereas you use the noun "dinner" instead of a verb or verb phrase like "dine" or "have dinner".
Is that picky? Yes indeed. Should DL be that picky? That depends on your philosophy of how language should be taught -- and on the limitations of a computer program!
I wrote "I am having dinner at my parents'" realizing that I would probably be marked wrong for using the present continuous to refer to a future event, but also I did not use "place" at the end. DESPITE this, I think the construction is a correct translation. What do you all think?
If you say "I am going to have dinner at ...: , that is also present continuous, and it is what the French here is more literally saying. I hope you wouldn't be marked wrong for that.
As for the rest of your suggested sentence, I think the English is just a shade off. I would suggest either "with my parents" or "at my parents'" (with the apostrophe) or "at my parents' place".
Further to my first point, it is true that in English "I am having dinner with my parents" and "I am going to have dinner with my parents" can both be used to express a near future event. (Of course, the "I am having dinner" variation can also be used for a currently occuring event -- right now -- which can confuse a computer program like DL's).
Even when two sentences are very close in meaning to each other, the fact remains that one of them has been said and not the other. You are always better off translating what was actually said as closely as possible, to the extent that the idioms of the languages involved permit.
I said "I an going to dinner at my parents' place" and it was wrong. My mistake. French is an interesring language. It appears to be more specific. No doubt that I will be partaking of a meal with diner. This is such an amazing language. It has certainly been challenging. For me it isn't frustrating as my ear becomes more attuned to the voices...especially the female. The rules, etc. will come with time and practice. J'aime la langue française. :-)
Referring so someone's residence as their "place" is common in English, although somewhat informal. See https://www.collinsdictionary.com/dictionary/french-english/chez