How to organize wi-fi with authorization?

Question

WiFi

There is a local network with Internet access and a database with user accounts. You need to install a wifi router so that users can connect to the network without a password, but at the same time they cannot access the Internet without authorization. As I understand it, for this you need to use the captive portal technology. I found an option on pfSense, but it's on freeBSD, so I'll have to use a virtual machine.
Tell me some option that can be organized on windows 2003.
There is a lot of information with authorization via SMS, but you need it with existing accounts.