Essentially each of us have two types of power
1) A sphere: which is related to how short or long or eyeball is
2) A cylinder: which depends on the shape of our corneas and the axis in degrees at which the cylinder power acts
There’s no need to calculate the power as you will require to wear glasses with both these corrections in place in order to see clearly
Health Tips
Since your cylindrical power is high, please visit your Ophthalmologist every 6-12 months to make sure that number is not increasing drastically, as it can be leading to a condition called as keratoconus.
Also please do not rub your eyes