I just launched a new website, however I've heard from a number of YouTubers that page speed is a key factor in website ranking. But I'm not sure how to monitor the page speed or fix the problem.
They are right website, speed is key along with good useful content to get ranked on Google. You can check your website's speed here, https://tools.pingdom.com/.
Your website speed is the time your webpage takes to load on the browser, shorter time your website takes to loan, better is its performance. Website that loads are loved by Google as well as people. However, just because your website loads faster means it will be ranked high. There are other things to consider.