VPN setup using 2 GL-MT3000 and a modem with a sim card

Hi,

I need to set up a VPN using Wireguard/OpenVPN that uses cellular data from a sim card that has to be physically left at home. In points, what I want to do:

  1. As an internet provider, I need to use cellular data from the sim card which is left at my home location.
  2. Internet can be shared via Modem/Router to VPN server which is setup by my GL-MT3000 device.
  3. Another client device (also GL-MT3000) can access the VPN outside my home location which ultimately uses the cellular data from the sim card.

Questions:

  1. Is that possible to setup in such a way?
  2. What requirements should the modem/router for the sim card have? I.e port forwarding option, something else? Any models that will do the job for sure?
  3. Are there any other differences in setting this up than when using normal ISP (e.g. normal home WiFi).

Thank you for help.