how to create a moving widget ?

examples :
1- when i press a certain button to pause the game , the widget options (play , options and exit ) plays sliding animation , like when i press pause button the widgets will slide from left to right , or whatever.
2- make a movment for the widgets to make them look as they are floating

HTF do I? Change Widget Positions in UMG using Animations - YouTube look at this tutorial

Use the animation window in UMG. Add a new track and select your widget in your case the button. Then add key frames within the timeline to animate.
Refer to this official docs for help: