The short answer is yes. ;) You can do all those things. I well remember the day I realized that I could do anything in MS Access. (now be kind this was the first experience I had in programming)
You can reference Parent controls from subforms with this convention Me.Parent.control
For example if the Parent form has a text box named txtEmployeeId then on the Click event of a text box in the sub form you could have this code.
Me.Parent.txtEmployeeID = Me.txtEmployeeID
You can quickly extend this code to do whatever you need ie.
Me.Parent.txtComputerName = Me.ComputerName
Me.Parent.cboProductName = Me.ProductName
CRUD is a statement used in web development which seems to be where you are coming from. Access is CRUD in many ways (unless you start getting complicated) In the example above, once you navigate off the parent record with the record selector or close the form, the record is saved without any code being written. Once you start playing around with unbound controls then it becomes necessary to write code to save your work.