You are not eligible until the second or third quarter after the calendar quarter in which you first worked. For example, if you began work in October or November, then you are not eligible until April or June.
You also must either (a) have made $1300 in any one calendar quarter (not including the one when you apply or the one before that) or (b) have made $900 in one calendar quarter (not including the one when you apply or the one before that) and made 1 1/2 times as much altogether during the four quarters that they consider as you did in whichever quarter was when you made the most.
You do not have to work any specific amount of time. In theory, even if you worked only one day, if you made enough money and you wait long enough to apply, then you can get unemployment.