How to get which editable text box is selected

I’m trying to create a virtual keyboard for touch monitor and I have more than one editable texbox, so how to find which editable textbox has the cursor to type, I’m using Blueprint so through BP I have to find.

I have wrote for each and every button in blueprint

If I press Q that directly goes to Mail ID Textbox, how to get which text is selected so that I can print that Q in particular textbox in blueprint

Awaiting for your help !!!