Realistically most people can only grow hops, not barley.
You can only really grow barley if you have a ton of acreage, and proper ways to actually malt/roast said barley in a controlled fashion.
Hops on the other hand are easier, you just need a space that is 20 feet or so that you can grow upwards...either build some type of post to let it grow up, or there are plenty of hop trellis designs out there on the web.