Supplier bank account creation, Need to know how account owner is fetched with the organization

Summary: Customer is trying to add the bank account for the supplier in the supplier site level, After adding the supplier bank account, Supplier is try to add the account owner, Need to understand, How the supplier account owner able see during the search of the account owner, Also need to understand how the party number is generated, Is it possible to search for the supplier using the party number.

Also on the type organization stands for what. Please refer the attachment for your reference.

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