Hi Pete,
nice project for a start! The Motion magic isn't that demanding, but I notice, not easy to find 'matching' pix… so, forgive me my tinkering to put such a plane in such a hangar, mismatching perspectives etc, but generally spoken:
so, what I've done here:
pic of a hangar with closed doors
pic of a plane inside a hangar
in a first step, I comp both pix: the hangar on a higher level, adding an inverted Mask to unveil the pic of plane inside.
Next, a new Group, again that Hangar pic (with closed doors), Hint: click/hold ALT and drag the pic a layer above=duplicates the pic in a New Group.
Apply a Mask, this time to select a door only.
Repeat steps for each of the 4 doors.
Now, to open, select each Door Group, set a keyframe at its X-position.
Move playhead forward, change X-value to 'open' position of each door, set keyframe.
Done!
… using keyframes isn't the most sophisticated method (Move Behaviors are … 'better', Sequencing, yaddayadda), but for a start..... 😉