Steps of FS00 to clear Initial Stock Clearing Account?

Hi Gurus

I have moved this from Logistic to FI section. Very sorry for the multiple thread:

I have some simple questions:

During the inital stock upload via movement type 561, the following G/L accounts are affected:

(a) Stock Account will be Debited

(b) Initial Stock Clearing accounts will be Credits.

Question

1. I was told that FS00 is the Tcode to perform clearing the Initial Stock Clearing Account. Can anyone advise me about the step to do it?

Let say my GL Account for Initial Stock Clearing Account (Raw Material) = 12345, CoCd = SS01

What else should I do in FS00 to achieve the clearing?

2. What is the name of this new G/L account where we move the values from Initial Stock Clearing Account? Is it GR/IR account or?

3. Why do we need a temporary Initial Stock Clearing Account? Is it because if we post directly to the GR/IR account and it will affect the stock valuation which will then need a IR (invoice receipt) to clear it off?

Please help to answer each question.