The question ask "were the parents of hannah married to each other at the end of 2021. My parents were separated at the end of 2021. How do i answer this question?

[DanP0428]

Answer it Yes.  They are married until they are officially divorced.

[ErnieS0]

Your parents are married @hannah050801 as super tax contributor @DanP0428 says.

The IRS considers persons married even if separated if they haven’t obtained a final decree of divorce or separate maintenance by the last day of your tax year.

An interlocutory decree isn’t a final decree. However, individuals who have entered into a registered domestic partnership, civil union, or other similar relationship that isn’t called a marriage under state (or foreign) law aren’t married for federal tax purposes.

Filing status