Where do we write the code's to publish?

Answer 1

Switch to the 4th tab
There you will see many codes made by others.
Search for the + button in the bottom-right.
Click on it.
Choose preferred language.
Then enter code.
Save it.
Make it public if you want to.

Answer 2

Where do we write professional codes

Answer 3

What do you mean by that?

Answer 4

You mean editors?

Answer 5

I mean, If we create an Android app, game and a website, where do we write codes of this stuffs?