EACCES permission denied : 0.0.0.0:443

Question

I asked a question before which is in this link and @itgoldman answered that i should use https which was correct but my other problem is that when i wanna access to 443(the specified port for HTTPS) it gives me this error : EACCES permission denied 0.0.0.0:443 Note that 0.0.0.0 is an example ip address first of all here is my code :

const fs = require('fs');
const ws = new require('ws');
const wss = new ws.Server({port : 443,host: "example.com",path: "/hello/"});
const clients = new Set();
var httpsOptions = {
  key: fs.readFileSync("ssl key"),
  cert: fs.readFileSync("ssl cert")
};
const server = require('https').createServer(httpsOptions, accept);

function accept(req, res) {

  if (req.url == '/ws' && req.headers.upgrade &&
      req.headers.upgrade.toLowerCase() == 'websocket' &&
      // can be Connection: keep-alive, Upgrade
      req.headers.connection.match(/\bupgrade\b/i)) {
    wss.handleUpgrade(req, req.socket, Buffer.alloc(0), onSocketConnect);
  } else if (req.url == '/') { // index.html
    fs.createReadStream('./index.html').pipe(res);
  } else { // page not found
    res.writeHead(404);
    res.end();
  }
}
server.listen();
function onSocketConnect(ws) {
  clients.add(ws);
  console.log(`new connection`);

  ws.on('message', function(message) {
    console.log(`message received: ${message}`);

    message = message.slice(0, 50); // max message length will be 50

    for(let client of clients) {
      client.send(message);
    }
  });

  ws.on('close', function() {
    console.log(`connection closed`);
    clients.delete(ws);
  });
}

I searched on stackoverflow and in this link I saw that this error is for Unix-like systems but it was in cpanel's terminal of my website. I ran the command too but that didn't work. Any help would be appreciated.