so i followed van tech corner's (https://www.youtube.com/watch?v=TsOpO6O4xDE&t=1022s) guide on installing openwrt onto a raspberry pi with a usb/ethernet adapter because that is what i am trying to do, only I have a slightly different setup i am trying to achieve. i also want to change my current netgear router into an AP since it has better wifi coverage than the rpi4. and im trying to do this at the same time. i also have a switch i'd like to start using but i want to get this router situation fixed first.
so when following his guide, i get to the part where you change the LAN interface back to 192.168.1.1 and enable the dhcp server, after doing so i get the 'saved configuration' screen on luci but after going back to Network > Interfaces, i no longer have a ip address for my WAN interface and internet is gone, i can't even ping anything. and that is right around the point a bunch of questions start arising. i really don't wanna sound like im complaining or anything but im just going to list some of the questions i have and hopefully whoever takes a stab at responding will know exactly what im talking about. im just always better at learning something if there is someone here in front of me to explain it rather than typing out your question in a forum then going back to it over the next few hours/days to find the best solution.
so first, my current router sits at 192.168.1.1, should i change that ip address to 192.168.1.2 right before i do the reverse of the LAN interface so openwrt can have 192.168.1.1? also, within luci, should i be configuring anything to let openwrt 'speak to' my current router which im trying to configure as the new AP? i want to connect them both by ethernet cable but when connecting to that wifi, how can i know if my traffic is also going through openwrt and not just coming from my old router again? i know there are two changes i need to make in my old router, one to disable dhcp and the other to enable it to be an AP, but when should i make those changes? would it be easier/better to use the switch instead of the usb to ethernet adapter? and last, would i be better off installing one of those community images? the configured one's like helmi-wrt or wulfy or seeed? or stick to the vanilla openwrt version?
i know i've put waaay too much thought into this simple project and it shouldn't be this hard but i can't let this little raspberry pi defeat me!