How to install and config the settings of Forticlient in Linux Server w/out GUI

Hello,

My client's Forticlient is always disconnecting to their's Fortigate.

I can't find any resources for me to configure the settings of forticlient (ssl vpn) in linux server.

Or if somebody knows how to setup the Forticlient so that it won't disconnect just like when configuring the Forticlient in windows but it's GUI; they only use Commands for their linux server.

PS. Not familiar with the commands so please help me

Big thanks!