Nexus 5 Downgrade from Nougat

I have a Nexus 5. I installed Nougat on it and I can not use the wifi hot spot feature anymore nor the USB tethering. I would like to go back to factory settings and upgrade to Android 6 and get rid of Kinko root, Chromium and TWRP.
Can anyone tell me if it can be done and how?
Thank you.

from Android Forums at AndroidCentral.com - Ask a Question //forums.androidcentral.com/ask-question/758006-nexus-5-downgrade-nougat-new-post.html
via IFTTT