Imagem JS na tela
base_image = new Image();
base_image.src = 'img/base.png';
base_image.onload = () => ctx.drawImage(base_image, 0, 0);
just-saved-you-a-stackoverflow-visit
base_image = new Image();
base_image.src = 'img/base.png';
base_image.onload = () => ctx.drawImage(base_image, 0, 0);ctx.drawImage(image, x, y) // top left coords
ctx.drawImage(image, x, y, width, height) // scaled