Could anyone tell me how to request a quote to supplier the component parts in DOP?

Customer operation and requirements are:

1. Create DOP header.
2. Pick up the parts to be purchased from the product configuration of DOP.
3. Create a request for quotation to the supplier for the picked up parts.

I can't make a purchase request so I don't know how to create a quote request.
Please let me know if there is any good way.

Best Regards,

Nobuo Murata