I see. What people typically do is set up two subforms on their mainform. The main form contains the date. Once that date is selected, all the transactions for the date are listed in the subform. When a record in that subform is selected, the details of that transaction are listed in the 2nd subform.
The problem handling the data your way is how do you bind the controls to the underlying table/query? In other words, you are feeding a certain set of records into your main form. For the moment, let's say it's all records. Then when you click on a record in the main form, your subform gets filtered to just show the records that occur on the date selected on the main form. But what happens now when you select a record on the subform? You now wish to alter the main form's recordsource to show only the record that matches the one selected from the subform. You see where I'm going with this? It's all technically possible to do the way you want, but it's a bit convoluted.
What I would do is use the two subform approach. You can design the second subform so that it looks like it's part of the main form if you like.