False. Your creative or cognitive ability is not separated by right or left hemispheres. Many of the “artistic talent” that you have is dictated by multiple parts of the brain on multiple sides. Being “right-brained” in order to signify creativity is inaccurate.
Also, most people who are generally adept at a certain subject (i.e math, science, etc.) will be talented in another area that is viewed as “left-brain” oriented. You can be good at math AND be good at music.