I believe LumberYard is a Windows program.
From the Amazon Lumberyard support pages:
Q. What are the system requirements for building a game with the Lumberyard Editor and tools?
We recommend you use a PC with Windows 7 64-bit, 8+ GB RAM, 60 GB of storage, a 3GHz+ quad-core processor, and a 2+ GB DX11+ compatible video card.
Q. What device platforms does Lumberyard support?
Lumberyard currently supports PC, Xbox One, and PlayStation 4. Mobile support for iOS and Android devices is coming soon, along with additional support for Mac and Linux. Note that Sony and Microsoft only permit developers who have passed their screening process to develop games for their platforms.