How to organize a connection to the MSSQL server with a gray ip provider?

Question

VPN

Hello, literate people, please explain how to connect to the ms server with a gray ip.
There is the following configuration:
Server ip - 192.168.1.100\24
Router ip - 192.168.1.1\24
WAN router port ip - 172.18.167.177
external ip under which the server accesses the Internet - 185.59.56.146
As I understand it, the provider gives me a gray ip (WAN router port ip - 172.18.167.177) which is NATed on the provider's display and goes online with ip 185.59.56.146.
The mssql server is installed on the server, how can I organize a connection to it from another remote computer?
Softether VPN server is now installed on the server, the network is configured 192.168.30.0\24
The server has a virtual interface 192.168.30.100
The client connects to the VPN server, receiving ip via DHCP from the network 192.168.30.0\24
Connection to the MSSQL server goes up perfectly, but the question is how the VPN connection goes up if the client only writes the server’s ip address 185.59.56.146 in the connection string, as the provider’s equipment understands that the traffic that came to this ip must first go exactly to the WAN port of the router ip - 172.18.167.177, and then to the server's virtual interface 192.168.30.100?