I feel like im missing something here. This is pretty trivial and the comments i see are over complicating the hell outta everything. All you need is your VPN tunnel working. Personally i use wireguard for this. Then you just use nginx as the reverse proxy it talks to services on the other side of the VPN.

The nginx server config looks like

server { listen 443 quic; listen [::]:443 quic; listen 443 ssl; listen [::]:443 ssl; server_name my.domain.tld; http2 on; http3 on; quic_gso on; tcp_nodelay on; error_log /var/log/nginx/jellyfin.access.log; ssl_certificate /path/to/ssl/fullchain.pem; ssl_certificate_key /path/to/ssl/privkey.pem; ssl_protocols TLSv1.2 TLSv1.3; add_header Alt-Svc ‘h3=“:$server_port”; ma=86400’; add_header x-quic ‘h3’; add_header Alt-Svc ‘h3-29=“:$server_port”’;

location / {
    proxy_pass http://10.159.4.12:8096/;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
    proxy_set_header Host $http_host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forward-Proto http;
    proxy_set_header X-Nginx-Proxy true;
}

}