help creating a formula (maybe a mocros) in excel to calculate break entitlement

Hi there, i am trying to create a new break plan at my work and I need a calculation to tell us what breaks the employee is entitled to during their shift, I currently have a column for their start time, a column for their end time and then 4 columns each representing a different break ( 15 min, 15 min, 30 min and 60 min) and then a total hours column. I basically want a tick or similar to appear in the break columns when the employee is entitled to the break, so if the employee is on a 8 hour shift, they are entitled to 2 15 minute breaks and one 60 minute break, so I want a macro that will result in a tick in both 15 boxes and the 60 box when the start and end times are entered (I have already done the formula to calculate the total hours worked as that was a really easy one) Can anyone tell me what formula I need to do this? or even what calculation I need coz i am not sure.