Hi, Scarlett and welcome to the forums! Looks like Sportsfan has answered your questions (thanks, Sportsfan!). For future reference, you may want to make your topic titles a bit more descriptive. In this case, perhaps you could have titled it "Can I change the traits of an adopted sim?" That way, readers know exactly what it is you need help with.
As an added bonus, you'll be helping others who have the same question. A descriptive title gives your topic more chances of turning up when someone does a search.
Anyway, have fun here in the forums!