There are three behaviors you'll see between chickens.
If he used his beak to grab her neck feathers and tried to climb on her back, it's an attempt to mate.
If he dances sideways, he's hitting on her (or, if it's another rooster, telling him off). To do this, he'll lower one wing, then stutter-step in that direction. He will likely run into her too if she doesn't move. It's the chicken equivlent of "Hey baby - your place or mine".
If he's facing her head and raises his neck feathers & jumps at her, he's trying to find his status in the order of the flock.
None of these behaviors are usually anything to worry about.