Are you referring to where in a class program do you place the file definitions?
Here is an example of what this could look like:
class-id managedfiles.Form1 is partial inherits type System.Windows.Forms.Form. ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT StudentFile ASSIGN TO "STUDENTS.DAT" ORGANIZATION IS LINE SEQUENTIAL. FILE SECTION. FD StudentFile. 01 StudentDetails. 02 StudentId PIC 9(7). 02 StudentName. 03 Surname PIC X(8). 03 Initials PIC XX. 02 DateOfBirth. 03 YOBirth PIC 9(4). 03 MOBirth PIC 9(2). 03 DOBirth PIC 9(2). 02 CourseCode PIC X(4). 02 Gender PIC X. working-storage section. method-id ReadFile. procedure division. open input studentfile read studentfile at end display "no more" end-read close studentfile goback. end method. method-id NEW. procedure division. invoke self::InitializeComponent goback. end method. method-id button1_Click final private. procedure division using by value sender as object e as type System.EventArgs. end method. end class.