How to deal with work anxiety?

So I have my first day of orientation today at Walmart.

I have only had one other job before. I’m 19. I quit and didn’t work for six months because I moved cities, my dad was dying of cancer and passed away, I moved in with my fiancé for the first time. It was hell for months.

Well I have orientation at 3 today and I’m SOOO nervous. I don’t know why. Like to the point of feeling sick. Is this normal? Has anyone else been this way? What do I do to calm down? Thanks