The thing is you might want to change the dark blue shirt to white and no bottons. Thats fine, but dont you change the red coat to black, thats a disaster unless you cut this prada pants in shorts. (We have a highly admiration of people who dose that kinda thing to their prada pants).
A Belt..... well... Yes. But only go with super soft cotton tee of plain color, and no coat needed in this case. Choose the belt carefully, leather could be really promising, but the color is tricky, my suggestion? Extreme colors (Black or white).
Shoes.... If you guna wear this with a coat, then shoes material should be co-op with the coat type or at least look fit-in. Again, do it like the left picture. Safe, smart, and chic.