You will need a Windows PC, of nearly any type; for maximum enjoyment, you will need VR rig. Either an HTC Vive, Oculus Rift, a Samsung Gear VR, Google Daydream, or other VR goggles (including the Google Cardboard) and a cell phone.
You can develop these WebVR worlds even if you don't have a sophisticated Head Mounted Display (HMD) or VR Headset ; you can view them in flat mode on your regular computer screen. You can pick up a simple VR cell phone holder/headset (Google Cardboard or similar) for less than 20 dollars or even free in many places, so don't let hardware be a barrier to learning about the next great thing.