Can I saw laminate flooring with a kobalt keyhole saw

No, this will be utterly useless. You need either a circular saw or a jigsaw (power tools, not hand saws) Laminate flooring is rather hard & u will kill yourself with a hand saw of any type, but a keyhole saw is totally the wrong thing to use. You will need a sawblade with fine teeth to get a clean cut. Laminate flooring tends to dull the blade after considerable usage, so if this happens in a power tool imagine what will happen to ur arms if u try to cut it using a hand saw, plus u will never be able to get a straight, clean cut by hand.

Not really, as it is name suggests it is primarily designed to cut holes. Personally I would rent a12'' miter saw.