Welcome to Target and welcome to The Break Room.
You should have been showed how to clock in. When you first arrive, try to clock in, and if there's nobody in the area near the time clock, head to the Guest Service desk and let them know it's your first day. Also, I see you marked Sales Floor in the thread title. I'm a former Hardlines trainer if you need help or have any question. Additionally, there's plenty of helpful members here on TBR who would be happy to help you out. Good luck, and don't be nervous. We all had to start somewhere.
Enjoy the ride.