Can I get my commercial property in NY changed to being my primary residence for my son to live there, or do I also have to live

This may not simply be an issue about who lives or does not live in the residence. Also, the mortgage is not really the key to this question. You should consult with a real estate attorney to determine whether the zoning rules for your property allow mixed use or residential dwellings in teh first place. Absent that first question, you could be looking at serious violations. (or if you are competent to do so yourself you should do so.

I hope this helps.

Disclaimer: This answer is for informational purposes only and does not constitute general or specific legal advice, nor create an attorney client relationship.