Nginx Proxy Manager instead of Synology WebStation

I have installed Nginx Proxy Manager on my Synology NAS using the Container Manager, but I haven’t set up SSL encryption. I already have a Let's Encrypt certificate via Control Panel > Security > Certificate. However, I want to use Nginx Proxy Manager as a reverse proxy instead of Web Station to forward my Docker instances from http://dockerinstance:8000/ to https://dockerinstance:8001/. Is there a guide for beginners?

thanks a lot!