i not understand any of your working environment related questions,
but if you insist NOT to use processing to show some text
still can use the ( already loaded ) p5.dom.js for it
example:
var div;
function setup() {
createCanvas(400, 400);
div = createDiv('').size(200, 50);
div.html('click/move your mouse');
div.position(20,20); // brings it inside the canvas, disable to show it below
}
function draw() {
background(200,200,0);
timer();
}
function timer() {
if ( frameCount > 300 ) div.html(''); // 5 sec ?
}
as that is permanently active you can use it later for more info to user