Ultimately my goal is to server PMS on a local network in my car with access to the internet.
The solution I've been trying is setting up the pi to bridge wifi to the LAN using this tutorial: https://pimylifeup.com/raspberry-pi-wifi-bridge/
So the pi3 will connect to my mobile hotspot and with its LAN port connect to a travel tp-link router I have.
I'm able to get the bridge to work and PMS separately but not together. I'm assuming that some of the forwarding that is happening setting up the bridge is conflicting with hosting a PMS.
I'm open to a completely different configuration, and was really surprised I wasn't able to find someone else on the net with this use case. If there was an easy way to connect the travel router to my hotspot that would be ideal. However looking this up I only see people trying to use their hotspot to connect there home router using two routers.
I'm a web developer but have always been pretty terrible with networking obviously.
Any help would be appreciated.