Open VPN Issues - Please Help

Hi everyone,

Before I get started I am pre-warning you, I am not technical at all in comparison to some on here so things need explaining in dummies terms. I apologise.

I have been tasked with setting up a simple home system. Diagram will be below.

I am using a MikroTik RB3011 UIAS-RM as a router.
Internet via PPPoE in Ether 1.
Raspberry Pi as a webserver in Ether 2 of the 3011.
Thus far, this is fine. It is doing what I want it to do.

The issue I am having is setting up OpenVPN. I have followed multiple guides and none have worked thus far.
So see the diagram below. What I am trying to achieve is to set up the 3011 with OpenVPN to allow simple access to it via 1 laptop.

Any ideas/solutions would be appreciated.

Thank you,

R.
VPN Set up.jpg