As long as the rooster is fertile, there will be fertile eggs, though there might be the odd hen that won't submit to him.
If you notice that the feathers on the backs, wings or heads of the hens are becoming damaged, you might want to consider separating the rooster, getting more hens, or replacing the rooster with a gentler one.
Judging by your username, I assume you've got children at home. Roosters have been known to attack small children, and they can cause serious injuries. They can decide to attack adults too. If you're not planning to hatch eggs, I'd recommend that you skip the rooster for now. If you want one later, you should be able to find a well-behaved one that somebody else can't keep.