Add additional days/weeks/months based on user input

Hi,

I have three formulas which I would like to change based on a user input cell.

The user must select either High, Medium or Low. Based on that decision the formula will populate the amount of time given to complete the task.

e.g.
Cell H9
If High is selected then +1 Month
If Medium is selected then +3 Weeks
If Low is selected then +2 Weeks

What’s the cleanest way to achieve this?

Ideally I would like the solution within a formula rather than a lookup, if this is possible?

I have attached an example.

Love this Glenn! Worked brilliantly