Indeed, Apple Motion makes this cake, drag and drop easy, don’t even really need to keyframe it, but you can. Type the word you want, select the “Add Behaviors” gear-shaped icon near the top center of the viewer screen, under “Text-Energetic” is the bounce in behavior, hit the “apply” button and test it.
With image files it just takes a slightly different path. Drag the object up out of frame. In the transport control panel just below the screen, turn on the red button and slightly nudge the item out of sight to set a first keyframe. Push the “Play” icon and push it again a moment later to stop. Drag the item’s bounding box down into the frame to where it hits the imaginary “floor”. You’ll notice a red path line being created. hit play for a split second again, and stop. Drag the image up a fraction. Hit play and stop again, drag down a bit less. repeat for three or four bounces. Turn off the red button, now play back your result, and if any recorded keyframe isn’t quite right, you can drag it with your mouse pointer and play again until you like it. Go to save> save as template, name it, you can make the same bounce apply to every item in a stack of image layers.