When a person is having a seizure are they aware of their surroundings?

Depends: If you mean a convulsive seizure, then the answer is "no." There is a rare frontal seizure with motor activity but retained awareness. I'm an epilepsy subspecialist and I've never seen it. There are other seizure types (simple partial seizures and myoclonic seizures) with retained awareness. "Convulsions" without a gap in the memory are most often psychiatric, and not true seizures.