G-RAID with Thunderbolt 2 to USB-c?

Can I use (Apple’s or any other) adapter to connect my G-raid with thunderbolt 2 to my PC that has USB-C? Will it work?

Thunderbolt and USB-C are different interfaces. You wouldn’t need to use an adapter as the G-RAID w/ TB2 also has USB 3.0 on it. You will just need a USB 3.0 B to C cable and you’d be able to plug it directly into your USB-C connection on your system.