I can guide you on how to create multiple company files, Rosie217.

When creating multiple company files, you can add or set up a new one in QuickBooks Desktop.

Here's how:

1. Click File on the top menu.
2. Choose New Company.
3. From the EasyStep Interview window, select Start Interview.
4. QuickBooks opens a wizard that guides you through setting up your new company. Follow the on-screen instructions to enter the information for your new company file.
5. You can export lists from your old file and import them into your new file, so you do not need to set up any lists in the wizard.

You can check out this article for more details about creating a new company file: Start a new company file.

I've got an article for your reference about creating a new company file to replace your existing company file:

• Create a new company file from an existing one

You can always reply to this thread if you need anything else with creating multiple company files in QuickBooks.