Only available as hydrogen fuel after you separate the carbon in the hydrocarbon molecules. Steam-reforming of natural gas will produce hydrogen, but at a far lower efficiency than using the natural gas as fuel in the first place.
Unless you use taxpayer dollars, it won't make economic sense to use hydrogen as fuel.
I don't think the efficiency is all that much lower...even with the steam reforming step. It's better than gasoline. Not quite as good as with burning of methane directly.
But, it matters not. There is NO WAY we're going to pump hydrogen everywhere for distribution centers. It's just too difficult and dangerous to handle.