You are not required to file a tax return. If you have no income, there is usually no benefit in doing so. There are rare exceptions.
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 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).
If you have scholarships and grants (not loans) that exceed your qualified expenses, by more than $12,200, you may owe tax on the excess.
