How do we create animated videos like these? Please explain?

They use "After Effects", but you can learn more or less similar video making at "goanimate"

Those are called infographics, and I agree that they were most likely done in After Effects.  I found a playlist of tutorials on Youtube that you might find helpful for learning some techniques: infographics tutorial - YouTube

While I agree  with Colin it probably is After Effects you could easily do all that with Animate and honestly I think it would be easier because you can draw the assets in the program instead of in say Illustrator and then importing everything.

You could ask the company what tools they used to make the videos:

Kurzgesagt – In a Nutshell Contact

My guess is they used After Effects. They seem to have a big team,  I'm sure each animation takes a long time.

On the twitch tv Adobe channel there are a couple of animators. Look at the schedule here:

Twitch

In particular, look for keyframer on Thursday, you could  watch that session and ask him questions about how to animate like is done in the video. He also has a YouTube channel where he posts his previous session, but of course you can't ask him questions in those! Here's his channel:

Chris Georgenes - YouTube

Beyond that, if you want to know how to do animation in Adobe Animate, there are lots of beginner tutorials on YouTube, as well as training sites like lynda.com