To take a screenshot on an Samsung Galaxy S21 FE phone, you must press the Power key and the Volume down button at the same time.
For Samsung phones, there is an original way to take a screenshot, this is to hold the edge of your hand across the phone screen from left to right.
As a result, the screenshot will be placed in the gallery. After that, you can use the image to share it on social networks, instant messengers, or keep it as a photo.