Martin Splitt of Google in the video goes through using the mobile friendly test, Search Console and Lighthouse as some ways to do this.
Here is the video:
Are you wondering if Googlebot can see your content? 🤔
Watch here → https://t.co/6LeBeafWWX pic.twitter.com/Uil3KaajBR
— Google Webmasters (@googlewmc) March 20, 2019
Forum discussion at Twitter.