I have Medicare disability can I still get medical coverage if I go out of the country for a month?

if you're asking what happens to your enrollment if you have Medicare & then move or stay aboard for a while, it's not a problem. You just need to make sure that you have a US address for Medicare (and for SS too) enrollment. Lots of folks retire abroad and fly back to the states for care. Depending on where live in the US, there could be private mail services to become your address for everything stateside and they DHL your mail to you where you live abroad weekly, monthly, etc so you keep current. Some hospital systems have programs for those living abroad too - like in my city, Oschner Hospital has Brent House where you & your family can stay when you come up for your hospital stay or medical appointments. I'd bet other bigger hospitals systems do the same.

Medicare health care you get while traveling outside the U.S. isn't covered. The 50 states, the District of Columbia, Puerto Rico, the U.S. Virgin Islands, Guam, the Northern Mariana Islands, and American Samoa are considered part of the U.S. Other than that you are on your own.