There are two hinged joints, between the two panels and at the top of the top panel. You can seal both these joints tightly by installing a soft foam gasket in each joint so that it is pinched when the door is closed. Make the gaskets very soft so they do not interfere with closing the door.
Seal the bottom of the door using standard rubber weatherstripping that is widely available for installing on the bottoms of garage doors.
A sliding seal is best for the sides of the panels. If the door is installed inside a jamb, install the seals inside the jamb. If the door butts against the outside wall, install a channel along each side of the door, and install sliding seals between the channels and the sides of the panels. The side seals will increase the difficulty of closing the door fully. Make sure that the door operator is rigged to provide sufficient closing force.