Let me show you how to create a bill in USD, Elena Roshchupkina1.
You can assign a currency when setting up a vendor. Once you save it, we're unable to change it. Go to the Expenses tab, select Vendor/Supplier, then click New supplier or New vendor. You'll see the I pay this supplier with section.
This is how it looks like:
You'll want to make the vendor inactive and set up a new profile. That way, you can assign and create a bill using USD. I've added these links for more details:
Keep on posting if you need anything else. Stay safe!