What is the adoptive child worksheet? I don't have children nor have ever adopted a child.

Please try the following options to address this issue:

With TurboTax Online open, go to "My Info," which should generate "Personal Info Summary."  If this screen shows a dependent that you didn't intend to enter, use the trashcan icon on the right to delete that information.

If that doesn't apply, go back to the Personal Info section where you add dependents. In the screen, "Tell us about your child", check to see if you inadvertently clicked on the radio button that says "Adopted" next to "This child is".

If that doesn't apply, and you are seeing that Form 8839 Qualified Adoption Expenses is in your return:

Here's the general procedure for viewing the forms list and deleting unwanted forms, schedules, and worksheets in TurboTax Online:

1. Open or continue your return in TurboTax.
2. In the left menu, select Tax Tools and then Tools.
3. In the pop-up window Tool Center, choose Delete a form.
4. Select Delete next to the form/schedule/worksheet in the list and follow the instructions.

Please see this Help article for other Tips and tricks concerning deleting other forms that may have transferred from last year's return.