Do Chromebooks Support Flash?
No! Flash is dead.
Google used to maintain a version of Flash that was integrated into the Chrome browser, and Chromebooks, via the Pepper API (PPAPI). This version of Flash was updated along with Chrome OS automatically when your Chromebook updated. Auto-updating of Flash was convenient and also a security benefit as users did not need to manually update Flash and could not be tricked into downloading fake Flash upgrades (a popular method of infecting Windows computers with viruses). Some have even suggested that Chromebooks offer the safest environment for browsing Flash enabled sites.
Since Adobe no longer supports Flash on any platform and it is considered a major security risk, it’s no longer possible to use Flash on a Chromebook.