If you're using Google's business-focused G-Suite service, your administrator will need to turn on the features before you can use them. The new features might not be available yet for everyone, and some of the more significant changes are yet to come. One of the biggest is called "confidential mode," which gives you the option of sending an email that requires the recipient to enter a code sent via text message before opening an email. You'll also be able to set messages to "self-destruct" after a certain period of time, and to prevent users from having the option to forward, download, print, or copy a message. There are limits to this scheme. Users will still be able to take screenshots of messages. But it could provide an additional layer of control over sensitive communications.
Google also plans to use artificial intelligence to identify the most urgent incoming emails, and allow you to limit mobile notifications to these. It will also try to identify mailing lists you can unsubscribe from by keeping tabs on how often you actually read messages from lists, and how long it takes you to open those messages. Another new feature, "Nudges" will, well, remind you about emails that you haven't responded to.