Is this device any good for fast Cycles rendering?

I found this device from Microsoft store

Nope, it’s worse than your standard desktop you can build for the same price.

Cycles renders fastest on the GPU, the page doesn’t list any GPU’s for that device.

Alright I’ll just go for a gaming laptop maybe alien ware or asus.

Why a laptop though? Does it need to be portable?

See this page.
https://docs.blender.org/manual/en/dev/render/cycles/gpu_rendering.html

Make sure the GPU in the desktop or laptop you want to buy supports OpenGL(AMD) or CUDA(Nvidia).

I choose laptop because electricity on my country is unstable I’ve got one big project corrupted because power went out so I sold my desktop PC for a laptop.

If you can afford it the mobile versions of the latest GTX 1070 and 1080 are phenomenal and nearly identical to the desktop alternatives, from what I’ve read at least. Between the two, for Cycles rendering, your best value for your money will probably be with a 1070. You pay 40-50% more for the 1080 with only a 10-15% performance boost as I recall. Check out http://blenchmark.com for more scientific(ish) comparisons.