Too nervous to work

I am almost 21 years old and I've never had a job which is sad. When I need money I will help my dad out. I don't work because I'm too anxious for face to face interactions with customers and other employees. I have an awful memory so I'm afraid someone will come up to me and ask where something is and I will have no idea and I will look like an idiot. I've though about doing stocking at night so I don't need to talk to customers but that's a lot of memorization as to where each item goes. I've thought about delivering pizza so I'm not really talking to any customers except for those 30 seconds I drop the pizza off but I might deliver to someone I might know, or I might panic and not know how much change to give them. I need to and want to start taking more responsibility and to get a job because it's pathetic that I've never worked a real day in my life before. I need money and if I work that will take time out of my day that I would spend fapping,edging,watching movies,playing xbox, ect.

 

It's easier said than done though