You're welcome. I tried to do basically the same thing a few years back (run a WordPress site from a RPi on my home network - and also a Minecraft server) and so I tried to write up the problems I ran into - I probably forgot some, but those are the major hurdles. I learned a lot along the way.
I should also point out that if you rent hosting space (from linode or inmotion or digitalocean or many other options) then problems 1 & 4 become much easier, and 2 & 3 go away entirely (most people don't host public websites on their home networks because of these and other issues).
Happy to help. If you're interested in learning networking more thoroughly, I want to point you to Professor Messer especially the Network+ content. He has far more complete explanations than I could write (and it's free!). Even if you're not interested in getting any certs, the explanations will be helpful.