QTY Column in sales invoice shows total stock? how to remove that?

The qty column shows the total inventory as well. How do I remove that.

I assume you are using Unit name field under Inventory Items incorrectly.

Unit name is meant to contain name of unit such as Kg, Ltr etc. Not quantity.

So go to Inventory Items and edit your items so they either have nothing entered in Unit name field or correct unit name (not quantity)