Question

meaning of tbis line???...
.....the president shall not withhold his assent from a money bill​

Answer 1

president cannot refuse to give assent to money bill...it is obligatory for him to pass the money bill

Answer 2

When a money bill is presented to the president, he may either give his assent to the bill or withhold his assent to the bill but cannot return the bill for reconsideration of the house. Normally, the president gives his assent to a money bill as it is introduced in the parliament with his prior permission.

hope this will help you