Hi Nitisha
You did not phrase your question well, but if I understood you right, you are asking about mapping products to product hierarchy
How to map?? - business people should tell you
Where to map?? - you do this in Material master, Basic views
In standard system, prod hierarchy is 3 levels. You can increase it up to 5 levels. The moment you activate prod hierarchy in SD, automatic derivation rules get added for the same
Br. Ajay M