First of all set the RecordSource of your subforms to an empty string "" this is a good practice in most situations because it allows your forms to load faster.
As an aside:-
It's possible that you have 7 subforms, one for each day of the week. I would avoid this unnecessary duplication and complication! I would use a single form to represent "a day" ("sfrmDay") this form would be used 7 times in each of the "days" subform subreport controls.
Now on your main form I assume you have some way of selecting the person that the timesheet relates to, possibly with a combobox. Add code to the after update event of the combobox to update the RecordSources of the various subforms
You need code that looks something like the following:-
Me.subFrmWinForYourForm.Form.RecordSource = "SQL Statement"
Where "SQL Statement" is a string representing the set of data you want to display in each particular subform
Where "subFrmWinForYourForm" is the name of the subform/subreport control which houses your subform.
".Form." refers to the Form contained in the aforementioned Control.
".RecordSource =" refers to the Record Source of the aforementioned Form.
Regarding adding data from the main form to each subform. You are falling Into the trap of thinking about the problem from the point of view of forms and subforms.
Imagine the following scenario:- You are creating a Christmas list.
Some tasks you perform on your data you do manually, like checking off customers who will receive a bottle of plonk for Christmas. Over the years, as the number of your customers increases it can become a chore. You realise an update query based on some criteria, like total order value for the year would be a better option, so you write a suitable query. What have you done? You replace manual actions on the form with a query which operates directly on the underlying data.
So think about your problem from this point of view, how can you add the data from the main form directly into the table?
I recently created a
playlist on my YouTube channel called "Subform" - Basically - I went through all my videos and just tagged ones with "subform" if they contained any mention of subforms at all! Hopefully there will be a bit more information about setting this up on subforms if you need it..