ATL is a huge airport.
You will not change terminals.
There are 2 terminals at ATL, one is domestic and one is International, but terminals are merely for check in, immigration, and so on.
You'll only need to change concourses (often mistaken for terminals). Terminals are at both end of the airport, and the concourses lay in between
You'll need to go from concourse A or B al the way down to cincourse F. You will take the subway system (plane train). You could be tempted to walk instead of waiting for the next train. Don't! Yiu'd need over 5 minutes between each concourse and you might need to walk past 5 of them (25 minutes) whr' the train will get you there in under 5 minutes total
Plane doors will close 20 minutes before scheduled departure (meaning you only have 24 minutes to land, taxi, deplane, change concourse, go to gate, board plane)
Your connection is hyper tight if all goes well. Delta considers a connection of that type to be illegal if under 40 minutes. That's how tight your connection is. But you want to have at least 60 minutes for domestic to international
It can be done but no way I'm attempting it
Delta is good at rebooking you for free if they have changed your flight to a shorter connection, so call them. If you've booked through a TA it's trickier as you'll need to go through the TA which might try to charge you