Hi LearningRPA,
Not sure if you are using a tab in a web or a desktop application but are you unable to spy the tab element?
For your reference even the tab on the Blue Prism main screen (that says Home | Studio) can be spied and easily be clicked on whichever tab we need.
To clear a textbox, after spying it, you can use a Writer stage to write a blank string "" to that textbox.