Go to Booking →settings → Pricing Parameters
Click on New Pricing
Give the new parameter a name
Set the price
Select the preferred group or leave the default group
Set it as active or inactive
Choose the display order
Give it a time duration in minutes
Link this parameter to the corresponding services
Click create
Go to Booking →settings → Pricing Parameters
Select a pricing parameter and click on the edit icon
Change what you must and click update
Go to Booking →settings → Pricing Parameters
Select a pricing parameter and click on the delete icon