SD Transaction Code Flow?

Inquiry / Document type IN
Tcode for creation VA11,VA12,VA13. tables VBAK,VBAP

Quotation / QT
Tcode for creation VA21,VA22,VA23. tables VBAK,VBAP

Purchase Order PO Tcode for creation ME21,ME22,ME23. tables EKKO,EKPO.

Sales Order OR
Tcode for creation VA01,VA02,VA03. tables VBAK,VBAP

Delivery LF
Tcode for creation VL01,VL02,VL03. tables LIKP,LIPS

Billing MN
Tcode for creation VF01,VF02,VF03. tables VBRK,VBRP

To create a sales order we need purchase order number and custmer number. Before that, to create a purchase order we need to have material no, vendor no.

To create vendor tcode is
xk01(create), xk02(change) , xk03(display)
Tables are lfa1.

To create custmer tcode is
 xd01, xd02, xd03.
Table is kna1.

After creating sales order using this no we can create delivery note tcode is vl01.