I believe the world is neither flat nor a ball, and what you get buy withholding such information is the power to keep all humans as stupid sheep.

Now, your suggestions about different camera lenses does not really work.
On earth, a camera lens will show more or less of the scene in front of you.
And since the camera lens is round, it will distort this scene, more or less depending on the zoom.

However, when you are far enough out that you can see the entire circle that is earth, there isn't enough distortion to basically change the size of land masses. You have the entire entity in the picture.

You can see this if you take a camera with different focal lengths and make sure the entirety of the subject is within the viewfinder, and notice the lack of distortion.