Actual Spying
Being a spy isn't usually running around with a gun and shooting people that's in the movies, real spy's though are about intelligence gathering. Getting inside an organization (sometimes just a building) being undetected or not noticed. In the middle ages spy's usually pretended as beggars or plague victims, nobody cares about them nor give them attention its the perfect cover.
Nowadays with technology spy's suit up as delivery guys so they can enter buildings passing security. Spy's are trained to get information without asking it directly or entering a building without arousing suspension
Training- When I was in spy school this was one of the basic that we had to do. Go to a random coffee shop, then our handler (we call our instructor "handler") would point at a random person.
Our objective would be get the following information and store them without them being on guard or suspicious. We were given a certain time frame 30mnts.
The info we had to get was. There birthday, address, children or spouses names, bank name, company name, age...
If your going to this exercise you must build rapport first you can't ask direct questions like. What's your birthday? (Nothing really come good out of that believe me)
These are tasks you'd have to accomplish for you develop the essentials skills your gonna need on the field.