How to Change the Default Location for Screenshots on macOS

Step1: To launch the app, open Finder, select Go  > Utilities, and open Screenshot, or use the keyboard shortcut Command + Shift + 5.

Step2: Choose a location below Save to at the top of the pop-up menu.

Capture your screenshot, and this one will go to your selected location, as will any future screenshots.

Credit : https://www.lifewire.com/where-are-mac-screenshots-8691559