OpenWrt Wireguard Client site to site Ubuntu - Wireguard Server

In the video I shared, Two OpenWRT 1.Wireguard Server 2.Wireguard Client VPN connects without any problems.

In my system, the 1st one is at home. 2nd one is AWS VPS

1.WRT1200ac Linksys Modem (Wireguard Client)
2. Ubuntu on Amazon web Service (Wireguard Server)

On my Openwrt device at home, I connect to the Wireguard server installed on AWS vps via Wireguard client without any problem and all internet traffic in my home goes to the internet via VPN on AWS vps. However, what I want to do is to access my lan network connected to my WRT1200AC (openWRT) device at home via the internet in my office while VPN is active at home. In the video I shared, the friend does this with two openwrt devices without any problems. How can I do this between Wireguard Server (Ubuntu) Wireguard Client (WRT 1200ac Linksys OpenWRT Router) between these two? I hope I was able to explain. Thanks for your help. I need the settings on the Ubuntu side.

Are you saying there are three sites involved: home, VPS, and office?
There are two ways to link them up:

  1. Both home and office establish VPN tunnels to the VPS. These should have IP addresses in the same subnet. Then it is simple to route office to home by using the VPN "backbone" IPs as gateways to the respective LANs. The downside of this is that traffic from office to home is two-hop, and if a lot of data is sent there may be usage charges from the VPS.
  2. Office links directly to home. This requires a publicly reachable IP at home, and some routing and firewall tricks so that the incoming / outgoing encrypted office traffic bypasses the otherwise all-covering VPN to the VPS. I don't know how to do that offhand but I think it is in the wiki under offering local services and also a VPN client.