Here are concise, useful pieces about running FortiGate VM in VirtualBox (setup tips, limitations, and learning resources).
Try to ping the FortiGate VM IP from your host machine command prompt. If the ping fails, double-check that your VirtualBox network adapter 1 is set to Bridged and that the FortiGate CLI allowaccess command explicitly includes http and https . fortigate vm virtualbox
Fortinet offers a permanent free trial license tier for lab testing, subject to certain functional limitations. Upon logging into the GUI, a prompt will ask for a license. Select . Here are concise, useful pieces about running FortiGate