Available from HERE 

This is a browser based program so there is no need to install 

 

The first welcome screen is as follows. Click on the Cat icon labeled as "Try It Out"

 

Note that if you have signed in with your Scratch Login ID and Password then the cat icon will not appear. Instead you will have a link "Learn how to make a project in Scratch" as shown in the following screenshot.

You will have to click on that link to use Scratch. 

 

or

copy paste the following link in your browser and hit ENTER:

https://scratch.mit.edu/projects/editor/?tip_bar=getStarted

 

The Programming stage looks like as follows.

 

Let us learn some programming skills now. For this you will have to click on the sub menus under this menu item.