Getting a French IP address when you are outside France is not difficult. The only thing that you have to do is to use a France VPN service. As we all know, VPN is the best tool to hide and modify one's local IP address. This page aims to tell you how to use a Free France VPN service on different operating systems.
Obtain a French IP address on Windows, Mac and Linux
Choose "Europe" then "France"
Connect to a VPN server in France
Now you have obtained a French IP address on Windows, Mac and Linux
Obtain a French IP address on Android and iOS
The steps are similar. You may consult these two tutorials: