How to make animations like these ? I have tried with drawing on whiteboard and taking time lapse of it. However from videos, they looked like picture is drawn first and then erased by some software. Any idea/tips to make such animations ?
Any animation software. The picture is also a path along which the hand with pen is going. The picture is masked and then unmasked in "timelapse" fashion. There are also services like "videoscribe" devoted to only whiteboard animations.
They are fake.
Although they can be done in a real stop motion, or simply filming you drawing and then speeding up on post pro, there are tools to just grabbing a black and white image and apply the effect. Take a look at this: https://goanimate.com/
Other option is using an animation software. But animating the hand will be a pain.