In the following example, Kali Linux is running on the internet cloud at 61.x.x.142 and running the SSH service on port 443 (make sure you change your router settings on your internet router to point to SSH). From the internal corporate network, all the ports are blocked at the firewall level apart, from ports 80 and 443, which means insiders will be able to access the internet from the corporate network. Attackers would be able to utilize Kali Linux by directly accessing the SSH service over port 443. Technically, for the company it is inbound to outbound internet traffic:

Next, you should be able to use your internet system to communicate with the internal network.