Thank you for your question. The existence of magic is attested to in the Qur'an in the stories of Prophet Sulayman (as) (2:102) and Musa (as) (7:113 onwards for example). A definition of magic to separate it from other less well known sciences is "the use of najasat and demons to fulfill an outcome". Such practices do exist and can have an affect on people.
May you always be successful