FortiClient is a good antivirus, but only for business or enterprise users. Home users will find they’re paying for an overpowered solution that they don’t need.
If you want to protect your entire household, you’re much better off picking an antivirus with a good family plan — like Norton 360 Deluxe, which offers coverage on up to 5 devices. This is especially important when you consider Fortinet’s licenses start at a 25-device minimum, which is quite a lot for one household. That said, if you want to cover more than 5 devices, you should check out McAfee before considering Fortinet, as it offers unlimited device coverage.