This is a very important dua that we should learn. Our health is a precious gift from Allah. Here is a dua for health.

Allahumma ‘afinee fee badanee,
Allahumma ‘afinee fee sam‘ee,
Allahumma ‘afinee fee basaree,
Laa ilaha illa ant

O Allah, grant my body health, O Allah, grant my hearing health, O Allah, grant my sight health. None has the right to be worshipped except You. (three times)

O Allah, I take refuge with You from disbelief and poverty, and I take refuge with You from the punishment of the grave. None has the right to be worshipped except You. (three times)
[Abu Dawood 4/324]