In the cell where you want the total,
type
=SUM(E2:E32)
That won’t work due to the way Excel stores its dates. Lets say you work from 9-5 5 days a week. When you enter “9:00 AM” Excel stores the value of 0.375 which is short for “1/0/1900 9:00:00” and when you enter “5:00 PM” it stores the value of 0.708333 (or “1/0/1900 17:00:00”). When you subtract these you’ll end up with 0.333 (or “1/0/1900 8:00:00”). If you add up the entire week you’ll end up with 1.666 (or “1/1/1900 16:00:00”). If you attempt to display this in 12 hour format it will just display as “4:00 PM”