For code writing we will use Arduino Web Editor 

Sign Up/Sign In

You’ve three options how sign up too Arduino Web Editor – Sign in with Google account, Sign in with Apple or Sign in with email.
After sign in with Google or Apple account you need to create a username and agree with terms of use.

First page

Now you see coding section with your first sketch.
On the left side you have menu with sketchbooks, examples,  libraries, monitor, refrences, help, prefrences and features usage.

Sketchbook section allows you to create a  new sketch, upload your existing sketches, add folders and make some easy operations with sketch.

Let's start coding!