Minecraft Education Edition Tutorials the relevant one

let x : number = 0

Step 1: Welcome to the Tutorial @showdialog

My first screen

Player Event Driven Blocks

Coders can use player events to execute a block of code. Some different stuff

player.onChat("hello", function() {
})
player.onItemInteracted(IRON_SHOVEL, function() {
    
})
blocks.place(STONE, pos(0, 0, 0))

Step 3: Run your code

Put some blocks onto the stage

This is really hard

Click the run button