I can share some information on how to add another business account, @userjmegna66.
One QuickBooks Self-Employed (QBSE) account is equivalent to one self-employed business. If you have multiple self-employed businesses, then I suggest subscribing to another QBSE account. It can only track income and expenses throughout the year and estimate quarterly tax payments for a single business.
To know more on how it works, check this article: QuickBooks Self-Employed Overview.
You can create a new account using this link: New QuickBooks Self-Employed account.
Let me know if there's anything that you need or if you have any other concerns with adding a new business account. I'm always here to assist. Have a great rest of the day!