Chromebooks chromeOS use Android version over Linux or WIndows webroot AV software.?

Bought a Lenevo Chromebook today and was not aware the free Webroot AV offered with the Chromebook was not specifically for ChromeOS. I really had to ask search which OS version of Webroot I should get  because this  Chromebook also has Linux Beta on it. So I had to ask Linux or Android. And I read of course after installing the Android Webroot Protection that  Chrome OS doesnt even need it anyway? Best  Buy had it free so I guess there is no harm installing it.?  There is no compatible Web Browser specific AV from Webroot for a Chromebook Chrome OS Chrome browser. Which is odd because Webroot only directed me to a incompatible Web Browser AV to download AFTER the WEBROOT Digital Dowload installed.