Je (aller) au garage du quartier.

Explanation

The correct answer is vais
The correct sentence would be: "Je vais au garage du quartier." Which translates to "I am going to the neighborhood garage."
The subject of the sentence is "Je" (I), which is a first person singular pronoun, so the verb "aller" must be conjugated in the first person singular form, which is "vais".
Here's a breakdown of the other options:
allez (second person plural, "you go")
allons (first person plural, "we go") va (third person singular, "he/she/it goes") vont (third person plural, "they go")