Growing Pains as a “Baby Manager”

Hi guys, 23f here. Just graduated with an education in SCM (supply chain management) and was instantly whisked away by the grocery store managers at my current job to become a manager myself. The training was easy. Merchandising was easy. But the hard part is now managing people whom, for the last 6 years of working here (since I was 17), I have tried my hardest to be friends with. It’s kind of hard watching the light in their eyes die when I have to boss them around. Have any of you gone through the same? If so, how did you overcome it? I just want to know so I can be the best I can be as a manager, and as a leader.

TTYL how do I be a good manager to people who used to be my best buddies at work