Creating an employee work schedule that will calculate time worked

I'm fairly new to Excel but I need to create a work schedule for my employees that will also allow me to total the hours they are scheduled for their work week. So far I've created a fake schedule and am using Data Validation to create the shifts but I am stuck on how to give each shift a number value. For ex Shift 6-230p=8 hours. and if possible, let me know if I've scheduled enough people. For example our schedule operates with a minimum of 10 employees each day. I'm hoping there's a formula that will let me know if I've scheduled enough people for each shift for the day. Any help would be greatly appreciated.

I'm attaching the schedule I've made so far to try and give someone an idea of what I'm trying to do

Thanks