Hi there, tonjunee.
Thanks for reaching out here in the Community. I'd be glad to show you how to set up another company in QuickBooks Online.
The Online platform does allow for recording books for multiple businesses. Each of these companies requires a separate subscription. Here's how to get set up:
1. Visit https://quickbooks.intuit.com/pricing/
2. Choose Buy Now or Start Free 30-Day Trial.
3. Select a product (Simple Start, Essentials, Advanced or Plus).
4. Click Buy Now or Try it free to subscribe to QuickBooks Online.
5. Select Already have an account? Sign in.
6. Sign in with your previous or current user ID and password for other company subscriptions.
7. Follow the onscreen prompts to set up a new subscription under your existing log in.
I recommend checking out the following article for more info on creating a new company and adding subscriptions.
Please let me know if you have any other questions. I'm just a comment away.