As skkp has said Telon has some predefined section with each section has specific means as Initlasation, Input and output and termination section. which if browse the code will be represented as ADD section name.
This Section's when you add will be added either to custom code or data group.
For a Normal Cobol doesn't have this section's.
And if you Import the normal Cobol to TDF (Telon) i think it will abend and gives the abend description in the report.