Android 8 Oreo is the next thing for Android devices and everybody is working hard to bring it to their phones. Now Essential has implemented a special Oreo beta program for owners of its beautiful Essential Phone. Where Samsung allows you to install the Oreo beta (on the S8 and S8 Plus) via OTA update, Essential will force you to use ADB.
Essential does provide clear instructions but this can be seen as a natural filter that disqualifies anyone that doesn't really understand how Android works or understand what a beta is.
You will find, using the above link, a build for NM181C (for Sprint and Telus) and NMJ32F (for the other carriers)
Remember this is a beta and you will experience issues and bugs. Known bugs already include: high battery drain, Android Auto issues and app instability.