Yes, you're right. The option to add an accountant should be available in the settings. You'll be able to invite up to two accountants to assist you with your books. I'll show you how.
Sign in to QuickBooks Online as a primary admin.
Go to Settings ⚙ and select Manage users.
Click the Accounting firms tab.
Enter your accountant's info and hit Invite.
Your accountant will receive an email with a link to sign into your QBO company.
Your accountant will be asked to create a user ID before signing in the first time, unless they already have an account with Intuit Business Services.
Until your accountant signs in, their status will remain as Invited on the Manage Users page. After accepting the invitation, their status changes to Active.
If you can't see the Accountant tab, you can access your account through an incognito window because you may be experiencing a browser issue caused by too much cache on your browser. Use the following shortcut keys below:
Google Chrome: Ctrl + Shift + N
Mozilla Firefox: Ctrl + Shift + P
Safari: Command + Option + P
If it works, return to your normal browser and clear the cache. This removes all the internet files and allows your browser to function more efficiently. Alternatively, you can also use different supported browsers.