> and how to deploy a VPS The VPS is just a virtual server, you will use an nginx or whatever reverse proxy to map your domains/sub-domains to your services. So, the actual deployment process will be on your device, then the nginx will handle the rest, because they the only one have access to listen on 80 (http) and 443 (https). The nginx can reach your localhost, other can't, so host your services on 127.0.0.1 and choice whatever port you want, but it's recommended to be 49152–65535 because "This range is used for private or customized services"Wikipedia. Don't bind your services to 0.0.0.0 because anyone can access them using your VPS ip, this IP "In the context of servers, 0.0.0.0 means "all IPv4 addresses on the local machine". If a host has two ip addresses, 192.168.1.1 and 10.1.2.1, and a server running on the host listens on 0.0.0.0, it will be reachable at both of those IPs."Wikipedia.