I still need to incorporate the position each employee will work. Those include cook, cashier, prep, assembler, and maintenance.
I dont see that, presumably you have not got that far yet?

To include all staff up to a certain time...
=COUNTIFS(D$8:D$29,"<="&11/24)
Change the 11 to whatever hour you need
You later expand on that to include worker types just by adding extra ranges/criterias