There is more than one way to do this. But we'd need to know more about how your timesheet is designed at the table level and what data might link the hours on that sheet to a project before we can suggest a solution.
So at the table level I have job numbers that is a drop down list from another database that we maintain called job numbers. The hours are entered by the employees and they enter what hours they worked need to be tied to a job number based on what project they were working on. I used the formulaIf (JobNoSu = Job list Summary;Case (Install Expense Type = Work Type Su ; Install Total Hours Su + TimeSu ;QAQC Expense Type = Work Type Su ; Install Total Hours Su + TimeSu ;Delivery Pickup Expense Type = Work Type Su ; Install Total Hours Su + TimeSu ;Equip Cable Prep Expense Type = Work Type Su ; Install Total Hours Su + TimeSu ;Equip Staging Expense Type = Work Type Su ; Install Total Hours Su + TimeSu ;Equip Testing Expense Type = Work Type Su ; Install Total Hours Su + TimeSu ;Pre Build Expense Type = Work Type Su ; Install Total Hours Su + TimeSu ;0 ))meaning that if a job number matches job list summary ( my search criteria ) then it will match the type of work they did to that job number and add them together. In this calculation all items under the case are being calculated for install hours. Each day of the week has 9 slots to place what you worked for, so I did this for each day for each work type that we are computing. Those would be Install, engineering, programming, project management, customer training, and travel. When I run my report I get these answers for each record of time sheets but I need a record for each Job.
First, you have multiple fields where it would be a simpler approach to have a set of related records, one for each day's work by a single employee on a given project, maybe even more--depending on whether your employees work on multiple projects during the same day or not..
(I once worked as a tech writer on user manuals and other documentation and had to spread my hours each day over multiple "charge numbers" as my work applied to all them in most cases...)
Then, you can perform a find for all records in a given time range with a specified job number and produce a summary report with the total hours, etc. worked on that project. It can be just a grand total or broken down by each employee.
You could also produce a report of all hours worked over a given time frame by find all records in that range and then your report can break the totals down by project (and also by both project and employee).
All controlled by what find criteria you specify, how you sort your records and what sub summary layout parts you add to your layout.
Here's an old but still valid tutorial link on Summary Reports: Creating Filemaker Pro summary reports--Tutorial