I'm not sure how to answer that - there is a sense in which fields simply "are". Fields are the vector quantities representing gradients in energy levels associated with a particular force, in this case the electromagnetic force. Light, of course, consists of propagating waves of electromagnetic fields (which, like everything else, have a duality with particles), but it wouldn't really be correct to say that fields are made out of light; really, it's the other way around. You can release energy by nullifying the gradient (e.g. uniting opposite charged particles), so in that sense fields could be described as energy, but they also are other things, such as force, and entropy, or more accurately the absence of entropy.