Is Oculus only Samsung?

Oculus is a company. What product are you talking about that is made by Oculus?

You're probably thinking of Gear VR, which is a Samsung exclusive product built in collaboration with Oculus. To use Gear VR you do need a recent Samsung phone. However, Oculus Rift is a PC product you can use on your Windows gaming PC. Or, you can wait for Oculus Go, which is a stand-alone headset (no PC or phone required) which is launching later this year.