Samsung removed the Bixby key on the Galaxy Note 10 and 10+ and gave the on / off switch the dual functionality. They have changed the way you turn off the phone, and make capturing screenshots a bit more difficult. Fortunately, once you get used to things, it's not too hard.
Removing the Bixby key and retaining Bixby itself forced Samsung to perform several tasks on the power button. If you press the button for a long time, Bixby opens by default. Access to the power menu now requires two buttons: Power and Volume Down. However, these are the same two buttons that you normally use to take a screenshot, causing confusion.
To create a screenshot on the Galaxy Note 10 and 10+, you must press both volume down and power buttons fast . Unlike other Android phones, you can not keep the buttons pressed (this will bring up the power menu). I can not stress enough how fast this touch is. Press both buttons at the same time, release them immediately and you will get a picture of your display.
Depending on your preferences, you can use the gesture instead. The One interface of the Galaxy Note 10 is a gesture for taking screenshots. Swipe left or right with the side of your hand to take a screenshot. Make sure the side of your hand touches the screen as you move from left to right, and the screenshot will automatically be taken.