Animating several GameObjects is simple in Timeline. The easiest solution is to bundle them by parenting them in a GameObject.
Then on the Timeline, create an Animation Track and add the parent GameObject.
Then click record and make changes to the object. For example here at the start, I set the scale of the Text to (0,0,0) and the alpha of the images of the two buttons to 0 and near the end. At the end of the animation, I set the scale of the text to (1,1,1) the alpha of the two images to 255.
Now, the GameObjects are animating.
