If you have no income, you normally do not need to file a tax return.
If you are a student, over age 23, and are not claimed as a
dependent by someone else (e.g. your parent) you may be eligible for the up to
$1000 refundable American Opportunity (tuition) Credit. That credit is not
dependent on having either kids or earned income. You must be at least a half
time undergraduate student, at an eligible institution, and actually paid tuition (not just had it paid by
grants). Tuition paid by loans counts as paid by you (since you have to pay
that back, someday)
You school will sent you a form 1098-T. But, you claim the credit with or without it.
