You mean that you want the camera to see that wall for say 5 seconds and then move and turn to see the other wall.
If that's the case, one method will be open the project tab, and the properties tab of the camera, and the timeline, with keyframes (so you can see where the keyframes are). now go in the timeline to the point where you want the pan to begin. In the properties tab, make sure all keyframes are selected (on the right of each parameter, you get a pop-up menu (it's a stripe), select add keyframe. Now go further in the timeline and make your change of the camera to the new position. If it's correct new keyframes will be made automatically.
If it's to fast you can select the keframes by dragging you mouse over them in the timeline/keyframe editor and drag the more to the left or the right (try not to go up or down, that will ruin the animation as you might understand).
You also could place the camera, go 5 seconds in the timeline, press record, make a tiny tiny adjustment (so motion will automatically make keyframes) then go further in the timeline and position the camera as you want. Turn the record button off.
I don't know if there's a function to make an automated pan between 2 camera's.
