If you received no taxable income of any kind in 2024 there is no need or reason to file a tax return.
Unless you are married, then you should be filing a tax return as Married Filing Jointly even if one spouse has little or no income.
It depends. If you do not have any income, then there may be nothing to report. If you have income from self employment on a 1099-K, 1099-NEC, or 1099-MISC then you may need to file a return for self employment. See the filing requirements below.
It depends. If you are below the filing requirement then you do not have to file. Review the chart in the link below to see if you are below the filing requirement. Keep in mind this is federal rules and you may need to check your state filing requirements (link provided below).
If you have no income you have no reason to file a tax return unless you have a 1095A for marketplace health insurance. You say you are a stay at home parent. Do you live with the children's other parent? Are you filing a joint return with a spouse? Or are you Single? How were you and the children supported?
To be clear---since you did not ask about this---you are not eligible for any refundable child-related credits if you did not have income from working.