Bonour Joelle, allow me to respond in English.
The main thing would be to set up the router/firewall on the office network to forward all traffic on port 5003 to your computer.
Problem is going to be however is that your computer is just a workstation and probably gets a new IP address from time to time. The port forwarding is going to fail when your machine gets a new IP address.
If the business solution is important you should look into buying FileMaker Server and setting it up on a server machine that has a static IP address. That way you can your boss can access it at all times.