how to open multiple puppeteer instances without effecting it's speed

so what happening to me is when i open 1 puppeteer instance it would go fast a but the more i open the more time it need to load the URL + fill information is that a normal thing ?

const puppeteer = require('puppeteer');

(async () => {
  const browser = await puppeteer.launch();
  const page = await browser.newPage();
  await page.goto('https://example.com');
  await page.screenshot({ path: 'example.png' });

  await browser.close();
})();

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