Explain the entire process of Invoice verification from GR to Invoice verification in SAP with accounting entries?

These are the following steps:
A goods receipt in SAP for a purchased material is prepared referring a purchase order.
When the goods receipt is posted in SAP the accounting entry passed is:- Inventory account Debit

GR/IR account credit
A GR/IR (which is Goods receipt/Invoice receipt) is a provision account which provides for the liability for the purchase. The rates for the valuation of the material are picked up from the purchase order.

When the invoice is booked in the system through Logistics invoice
verification the entry passed is as follows:-
GR/IR account debit
Vendor credit