To view the MakeCode editor, go to https://makecode.microbit.org/ using the chrome browser
Then select "New Project"
The MakeCode editor consists of the following components
Simulator - on the left side of the screen, you will see a virtual micro:bit that will show what your program will look like running on a micro:bit.
Toolbox - in the middle of the screen, there are a number of different categories, each containing a number of blocks that can be dragged into the programming workspace on the right.
Workspace - on the right side of the screen is the Programming Workspace where you will create your program. Programs are constructed by snapping blocks together in this area.
The color of the blocks identifies their category. All of the blocks that make up the program above come from the Basic Toolbox category, which is light blue.