I want to learn how to build a phone, maybe something like the pine64 and librem phones. I'm a web dev so it's..challenging. How do I learn to:

* understand the hardware components required in a phone?

* understand the software components required? postmarketos and plasma mobile maybe?

* How do I even start to build a prototype? What components would I use? Maybe start with using a raspberry pi to make a DIY phone?

I know this is an open ended question, so any pointers would be appreciated.