Connect my app java desktop with my external server to the database

Hi, I have to connect my java desktop app to the database in the external server. In this moment I use a DDNS and I have the port open in the router (port forwarding) to connect de app desktop with the extenal, I know that it’s not safe .

Is a good idea use the service ‘Zero Trust Tunnel’ to connect the app with de server or is better other option? I have seen that exit WARP but I prefer no use VPN in my clients, besides I prefer not connect muy clients to the internal network for security.

Thank you so much!

Is this tutorial a good option for my problem?

Cloudflare Zero Trust Tunnels for the Homelab
https://tsmith.co/2023/cloudflare-zero-trust-tunnels-for-the-homelab

I have some doubts to difference the use between ‘Zero Trust Tunnel’ and the WARP for the VPN tunnel.

Thank you!!