Yes of course you can eat them, but it's true that you have to buy sprouting barley. Hulled or pearled barley will not sprout.
Here's a longer post about sprouting
. But I'm not THE expert on it
I rinse the berries, soak them overnight. Then I just put them in a plastic container and cover it loosely. I rinse them maybe once a day and wait until they sprout. They are ready when the tails are about 1/4 of the length of the berries, or even longer (few days max). When they are ready, I refrigerate them to slow the growth.
1 cup of berries will make a LOT of sprouts, you might want to try 1/2 cup first.
You can either eat it like cooked rice, add it to salads, etc - though you mayfind it too tough to chew. You can also grind it in the food processor into a doughball (adding herbs/spices/other ingredients), form loaves or cookies and dry it to make raw cookies and breads. But there are plenty of other recipes too.
Also, if you dry and crack the sprouted berries, you will have produced, if I'm not all too mistaken, malted barley, which then you could use to make your own beer!