If you own the HTC 10 in the US, you should be seeing a notification for the new software update. In case you haven’t received the notification, we’ve got the link full firmware file below. You can download the RUU file and install the update manually.
The software version of this new update is
3.16.617.2 and it is rolling out as an OTA. To check for the update manually, head over to the Software Update option in the Settings app and tap on the Check Now button.
Android 8.0 Oreo brings several new features to the device, including Autofill, Notification dots, Picture-in-Picture mode, improved battery life, Intant Apps, Smart text, and much more. Remember, this update is for the unlocked variant only, so we suggest you not to install it on other variants. Oreo update for locked carrier variants should arrive soon.>
Source : https://www.theandroidsoul.com/htc-10-in-the-us-gets-android-8-0-oreo-update/