Badi Requirement

Hi Freinds,

I am new enhancements, i have requirements on BADI's, can any one help me in this how to slove this BADI's

Points will be given

The BADI's are

1.The header text of the reference document is to be copied as well when purchase Requisition (PRQu2019s) are copied into purchase Order (PO)

2.Change Item data in Tcode MIGO, Customer specific storage location determination for the material id with item text

Can any one explain me in detail about this BADI's

Thanks and Regards

Vijaya