javascript into html

I am trying to create a javascript game because it can somehow link to html. So far I tried making the canvas in java script pop up but i only saw a white screen. I just started learning html and atm I want all my code to be in java and just use html to place it on the webpage.
here my html:
`

Space Invaders

`

i'm trying to link this page to my js

here my js
`function setup(){
createCanvas(400,400);
}
function draw(){
background(0);
}`

i'm wanting a 400 by 400 screen to appear on the web page with the background in the square being 0. Can someone tell me why this not working?

Inizia riproducendo gli snippet HTML e JavaScript forniti, usando l’entry point spaceInvaders.js indicato e le funzioni setup e draw. Controlla come la pagina carica lo script e come viene creato il canvas, quindi verifica che nella pagina web compaia un canvas di 400 per 400 con valore di sfondo 0.

Scritto dal modello di indicizzazione a partire dal testo della issue.