Is there a way to limit the number of connection made by an IP address to my Windows Server?
I'm trying to restrict the number of connections used by a single IP address on my server
Windows doesn't have a built-in mechanism for doing this in the host firewall. It may be possible to configure specific applications to only allow a specific number of connections, but since you've provided no meaningful details, there's not much to work with.
Your best bet is to control this type of thing on a dedicated firewall box that the server is behind.