Malala, 15, was speaking in an interview recorded before surgery at a Birmingham hospital on Saturday.
She was shot on a school bus in October in Pakistan by the Taliban after campaigning for girls' rights.
Surgeons at the Queen Elizabeth Hospital said Malala was recovering "very well" from the latest operation.
A bullet was removed from her head by surgeons in Pakistan, before she was flown to the UK for further treatment.
Malala was discharged as an inpatient from Queen Elizabeth Hospital in January and underwent a five-hour operation at the weekend to fit a titanium plate over her damaged skull.
She also had a cochlear implant fitted to deal with some deafness caused by her injuries.
Speaking in the video in English, Malala said she wanted to "serve the people".