Questions re: setup VPN into my home network

I am trying to connect to my home network from a remote location / hotspot to access my systems and the internet. I plan to use two GL-inet AR750S-EXT travel routers. One AR750S will be configured as an vpn client. The other AR750S will be configured as an vpn server. Between the vpn client and the vpn server will be a wifi hotspot, the internet / ISP, and a cable modem / router.

I’m trying to break this down into pieces / tasks to get a better understanding of what I need to do and the questions I need to ask.

wifi hotspot
cablemodem rtr

The remote network is probably going to be a laptop attached to the client / LAN side of the AR750S running a vpn client.

The wifi hotspot will probably be a hotel wifi.

The cable modem / router is currently an xfinity device. (My ISP)

The AR750S-Server is attached to a network connection on the cable modem / router and is running a vpn server.

Things I know:

I can test this at home using the xfinity hotspot to simulate a remote connection. There is a setting in the cable modem that, when enabled, prevents devices that have been attached to the lan or wifi networks from connecting to the hotspot on this device. I had this issue a while ago and disabled that option.

Need to assign a static IP address on my home network for the AR750S-Server.

Need to forward a port on the cable modem / router to the static IP address of the AR750-Server.

Questions - What I don’t know:

1 - Do I need an vpn service provider or can I configure one AR750 as the vpn server and another AR750 as the vpn client and somehow point the client to the server… was looking at openvpn…

2 - I generate the vpn server file on the AR750 to be used as the server, and also create the client
configuration that will get copied to the AR750 that will be used as the vpn client. Where are the files I generated?

3 - There is some editing of the vpn client configuration file in order to point the vpn to the IP address
of the cable modem / router and the port that is forwarded to the vpn server. where? when? how?

4 - I think I need some sort of dynamic DNS fucntion in order to determine the IP address of my cable modem / router. Can this be done on the AR750 vpn server?

5 - From the vpn client - How do I know the IP address of the server and that it has changed?

6 - There is a setting - ‘Allow Access Local Network: Enable this will allow every client that connect
to this VPN Server be able to access your LAN. Enabling this option will allow me to remotely connect to machines on my network.’ Is this what gives traffic coming in from the vpn access to my devices and out to the internet?

7 - Allow Access Local Network: - If I do not enable this, where does my traffic go? Do I define a
specific IP address / destination to route the traffic coming in from the vpn? Where do I define this
address? Does the vpn traffic just go to the internet? (prevented from going to local devices?)

8 - Am I looking at this correctly?

9 - Both WireGuard and openvpn will work.

10 - Port forwarding - is there a recommended port number?

11 - I don’t know what else I need to know…

12 - I saw where someone used the button on the AR750 to enable and disable the vpn.
I’ll save this for later… could be handy.

Misc. info:
Cable modem / router LAN IP address is I have a static range of IP addresses and a dynamic range of IP address on my network. I have one AR750 that I used to connect to an xfinity hotspot last year. The other AR750 arrived recently.

Any and all comments, tips, suggestions are appreciated.