You can create a custom tax and enter the rate for the reverse charge of the goods you purchase. But I'd still recommend contacting your agency for instructions since QuickBooks will always update and follow the tax rate mandated by your tax agency.
That being said, let me show you how to create one:
Go to Taxes.
Select Add tax.
Click Tax rate.
Enter the name of your new tax rate. Say Reverse Charge.
Put a checkmark on both Sales and Purchases.
Type in the rate with the correct amount (plus or Minus).
Additionally, I've got you this helpful article for the steps in preparing and filing your tax return: File and pay Tax/GST.
Keep me posted in the comments if you have any other questions. Stay safe!