Plan Driven Procurment and SC creation in SRM

Hi Experts,

Please clarify below queries with respect to plan driven procurement.

We are looking to interface data from external system to enable Shopping cart creation in SRM and thought is to create PR in ECC and convert this to SC using the Plan Driven Procurement settings.

Can some one confirm the dependencies here and is there still any manual intervention needed to create the SC in SRM or this will happen in automatic in SRM directly available for approval process?

Thanks & Regards

Kishore Murikipudi