"The restaurant at the corner opens at 10."
Please stop splitting words into different syllables and attaching them to particles or the beginnings of other words. This is difficult to look at.
Is it possible to put the time first and then the restaurant/location?
What is the difference between two examples? かどのレストランは十時にあきます、 かどのレストランは十時にあく。
あく is what we call the "dictionary form" of the verb. If you look up "to open" in the English-Japanese dictionary, you will find あく. You use the dictionary form for the present/future tense. All verb conjugations are derived from the dictionary form.
あきます is the "-masu form". It is used for the polite present/future tense. Duolingo only focuses on teaching the polite conjugations of verbs, as these are the most useful for talking to strangers.
Take a closer look at Japanese verb conjugation if you'd like to understand it further.