Let us know if you followed the steps below for installing forticlient vpn on Debian 11. If you would like to install it on your Debian machine, you can try to download the .deb file from fortinet.com/support/product-downloads#vpn and use dpkg -i <file name> to install.
And it also changes my nameserver inside /etc/resolv.conf with the ones stated on my VPN server, which kills my internet connection. I have to remove them and insert my router's IP in order to fix my connection.
The Fortinet Security Fabric brings together the concepts of convergence and consolidation to provide comprehensive cybersecurity protection for all users, devices, and applications and across all network edges.