A production version is a combination of a BOM and a routing that defines how a material is produced. For a production version to be valid and consistent, the following requirements must be fulfilled:
The deletion flag must NOT be set for the BOM or the routing. The deletion flag indicates that the BOM or the routing is no longer used and should be archived. If the deletion flag is set, the production version cannot be used for production planning or execution.
The lot size range must be within the lot size range of the assigned routing. The lot size range specifies the minimum and maximum order quantity for which the production version is valid. The lot size range of the production version must match or be smaller than the lot size range of the routing, otherwise the system will not find a suitable routing for the production order.
The assigned routing and BOM must be valid in the entire validity period. The validity period defines the time frame for which the production version is valid. The validity period of the production version must be within or equal to the validity periods of the routing and the BOM, otherwise the system will not find a consistent BOM and routing combination for the production order. Reference: [SAP S/4HANA Production Planning and Manufacturing Certification Guide], page 113; [SAP Help Portal: Production Version].

A scheduling agreement is a long-term agreement with a vendor for the supply of materials or services at predefined dates and quantities. To enable classic MRP to automatically create schedule lines in case of material shortage, you must do the following:
Add the agreement to the source list and mark it for MRP relevance. The source list is a list of possible sources of supply for a material, such as vendors, contracts, or scheduling agreements. By adding the agreement to the source list and setting the MRP indicator, you specify that the agreement is a valid and preferred source of supply for the material.
Set the creation indicator for delivery schedule lines on the initial screen of the MRP run. The creation indicator determines whether the MRP run creates procurement proposals, such as purchase requisitions, planned orders, or delivery schedule lines. By setting the creation indicator for delivery schedule lines, you instruct the MRP run to create schedule lines for the scheduling agreement, based on the material requirements and the agreement conditions.
Adding the agreement to the quota arrangement and marking it for MRP relevance is not necessary, as the quota arrangement is used to distribute the total requirements of a material among several sources of supply. Setting the creation indicator for purchase requisition on the initial screen of the MRP run is not correct, as the purchase requisition is a different type of procurement proposal than the delivery schedule line. Reference: Scheduling Agreement | SAP Help Portal, Source List | SAP Help Portal, MRP Run | SAP Help Portal.

Dependent requirements are the requirements for components that are derived from the requirements for the finished product or assembly. They are created when an independent requirement is created for the finished product or assembly, such as a planned independent requirement, a sales order, or a stock transport order. They are also created on assembly level during the planning run, when the system explodes the bill of material (BOM) of the finished product or assembly and calculates the requirements for the components based on the BOM structure and quantity. Dependent requirements can be created for multilevel or single-level BOM structures, depending on the planning strategy and the BOM explosion level. Reference: Dependent Requirements | SAP Help Portal, Material Requirements Planning (PP-MRP) | SAP Help Portal.