If you get married in Panama but reside in Maryland for over a year, do you have to file in the Maryland or can you file in Panama and it still be official?

Most states in the United States have residency requirements, check with your local clerk

If you get married in Panama but reside in Maryland for over a year, do you have to file in the Maryland or can you file in Panama and it still be official?

Overseas marriage is also recognized in US and other countries. If you've been resident of Maryland for more than 6 months, you can file a divorce with local court there. Also you can file in jurisdiction where your spouse lives.