There are many different Chromebooks out there with varying levels of support for Komodo:
Komodo on the Google Play Store
If your Chromebook has the Google Play app (not all Chromebooks will have this functionality), simply open Google Play, search "Komodo math" and install the Komodo android app. Once it is installed you should be able to find it within your applications.
This is the only option if available for Chromebook.