Yes, you can use the Samsung Galaxy Tab S10 Ultra as a screen extension. To do this, you can use the "Second Screen" function, which allows you to connect the tablet to a Windows PC as a second screen. However, this function requires that your PC supports Windows 10 or higher and has the "Wireless Display" (Miracast) feature. You can take notes on the touchscreen and then edit them on your laptop by transferring or synchronising the notes.