Start by creating a new project. Navigate to MakeCode for Microbit and click on 'New Project'. Give your project a name, such as 'Weather Station'.

First, we need to declare and initialize our two main variables: 'mode' and 'reading'. 'Mode' will help us determine which sensor's data we want to display, and 'reading' will store the sensor data. Add the following code:

let reading = 0
let mode = 0
mode = 1

The following are the different modes we will have:

1. is for displaying the temperature.
2. is for displaying the light level.
3. is for displaying the sound level.
4. is for displaying movement.
   

Let's start by configuring Button A. When this button is pressed, we want 'mode' to be 1. Add the following code:

input.onButtonPressed(Button.A, function () {
   mode = 1
})

Next, let's configure Button B. When this button is pressed, we want 'mode' to be 2. Add the following code:

input.onButtonPressed(Button.B, function () {
    mode = 2
})

Now, let's configure the combination of Buttons A and B. When both these buttons are pressed, we want 'mode' to be 3. Add the following code:

input.onButtonPressed(Button.AB, function () {
    mode = 3
})