I am a 21 year old woman with add. What vitamins would you recommend?

None. Vitamin supplements are not known to have any effect on add symptoms.
None necessary. As long as you eat a balanced and nutritious diet, there are no vitamins that are recommended. Having add does not change this recommendation.
Eat smart & healthy. Having add is not a factor. In other words, you should have the same vit's that you'd need if you didn't have add. Conscientious, healthy eating habits is the best approach to nutrition & it can supply all the vitamins one needs. It's reasonable however to take a standard multiple vit with iron. E was once the rage; now d is. Many young women need calcium(not a vit); folate(b9) is impt b4 pregnancy.