Is it possible?

Question

that single person who know's pragramming can make an app.

Answer 1

yep, plenty of people have created apps by themselves.

Answer 2

Of course, you only need 2 things:
• Basic understanding of programming
• An idea for an app
You might also need money to publish it.

Answer 3

Once you have a basic understanding of Java and the API (imports, implementation, etc.) system, it can be pretty easy to pick up on. Try this after learning Java (it's incomplete, but it has the basics):
Torch - Android Crash Course:
https://drive.google.com/file/d/1-fbu-aMFWixjUTVZxsYUBNnWcfrAKRY3/view?usp=drivesdk