Your grandparent may apply for a tourist visa at the US embassy in Port au Prince.

In general, the time it took USCIS to adjudicate petition, is deducted from child's biological age.

You may take your completed and filed current (2021) tax to the interview.

Go with USCIS officer recommendation in writing at end of interview.

You may consult an immigration attorney to look closer to your specific case for viable options.

It's up to Canadian authorities to admit you or refuse entry. Consult a Canadian immigration attorney.

It is up to courts and agencies in Texas if a spouse may refile child support after opting out.

Your question...." if my parents received Green Card, would they have to live in the United States for a specific period of time every...

No blank spaces are allowed. You must annotate "unknown" if appropriate.

The expired "stay away" order may not impact your application for permanent residency.