How To Effectively Teach Sunday School Class?

I'm not sure if this is the appropriate sub reddit. I'll be teaching Sunday school class in a couple of weeks for adults. My Sunday school teacher will be there. I honestly have no idea what I'm doing. I was given a video to play for class. I have experience teaching Sunday school for elementary-aged children but that was ten years ago. I'm afraid of having a panic attack during class. I thought about playing a song or read a Bible verse related to our study. How do you effectively teach Sunday school?