Starting balance qty is not showing while creating the items in inventory and also in version 18.10.96 how to update inventory value?
For starting balances, read the Guide: https://www.manager.io/guides/5497. Remember, though, that starting balances are only used when migrating to Manager from a previous accounting system.
What do you mean by updating inventory value? Inventory value is calculated automatically based on the starting balance (if any) and purchases made since.