There was nothing wrong with what Erica was doing but Steve felt he was missing something here.
He decided to meet with Lisa and talk to her about Erica and before that he had to apologize to her.
So, he first went to his home.
His grandpa loves gardening and Steve used to help him, so he plucked a few flowers from there and went to meet Lisa.
The town is small and travelling from one place to another didn't take much time.
Steve first went to Lisa's home assuming she would be there but her parents told him she is still not home and is probably partying with other friends.
Steve then went back to the prom party.