More than 140 devices are listed on the product page, indicating the device's internal code, kernel version, architecture, and deadlines for the device to stop receiving official auto-updates. Some devices on the page have been marked as out of support, meaning Google will no longer continue to provide updates for these devices.
On the "CVE-2017-5754 mitigations (KPTI) on M63?" Column, flagged whether this Chromebook will be affected by the Meltdown vulnerabilities, and if it is marked as "Yes" or "not needed", then naturally there is no need to worry.
For Specter vulnerabilities, Google offers slightly more protection. Chrome OS provides what is known as site isolation, which effectively reduces the damage caused by this vulnerability. If you want to activate this function, users can type "# enable-site-per-process" in the address bar of Chrome and mark this function as "Enabled" after Enter.