If they shoot a ship every few minutes, say 25 per hour, that would get them about 5 mil per hour on average.Yes. A beginner is going to have trouble locating opponents, flying to them and getting even a single shot in. They will kill a ship once every few minutes at best, without KWS scanning. For a true beginner even 1m is optimistic.
From what you're saying, I can't believe that you have any experience of using a Sidewinder in a high RES, like the one in Dromi, where the starter mission takes you. There are ships all around. I suggest you get a Sidewinder and go to any High RES, then come back and comment.