Hi there, trueluxled,
The invoice template may have been imported, and that's why you're unable to edit the current format. The Edit current is grayed out when you try to modify it. See the screenshot below for your visual guide.
With regards to the VAT that should show against each line item, you're unable to move them. QuickBooks separates the calculation per line item and they're located above the balance due to the invoice form.
Creating a new template won't still let you change the default format where the VAT calculation is located.
Feel free to leave a comment below if you have follow-up questions. I'm always right here to help you out.