You need to study the basics and make a reasonable
effort in struggling with the problem yourself.
This way, you will eventually be on the way to becoming
an expert in COBOL, and you will develop your problem
solving skills.
People can tell straight away if you haven't made a
reasonable effort, and usually will simply not help you.
I'm not "flaming" you - just suggesting you take the path
that I'm sure the rest of us have taken.
The longest journey starts with the first step.
People are not going to carry you all the way,
but they will help if they see you are trying.
Kindest Regards.