Wow, incredible info. I really appreciate this and will be doing a deep dive!

For the Graphene OS AOSP fork, these are the compatible phones: https://grapheneos.org/faq#device-support

You gotta make sure to get it "unlocked" so no buying a phone plan during the purchase.

https://store.google.com/category/phones?hl

Then follow the web installer instructions
https://grapheneos.org/install/web

Alternatively, you can do the don't install it yourself option (which is inherently sketchy and inherently opens you up to abuse) by buying a preinstalled one.

https://liberateyourtech.com/product/buy-grapheneos-phone-pixel-new/

nerd2ninja

Great advice. How complicated is this for someone that’s mostly tech savy but not to the level of being aware of AOSP.  What type of phone would this be installed on? My questions are probably a bit too simplistic but you get where I’m going. 

tech

Having alternatives in Tech

Don't switch from Apple to Google, switch from Apple to the Android Open Source Project (AOSP) and use Obtainium to install apk files from their respective github if you must.