SubScreen Animation

I have a main screen and 4 sub screens which they are in main screen as a child but only a subscreen is shown. Each subscreen has different type widgets such as text, image etc. I want to switch between these 4 pages with animation and definite duration and want the main screen not to change. So animation for only subscreens. How can I do this?

Screenshot from 2021-12-04 22-51-28

The first thing that comes to mind is animations. Animation function could gradually hide one of the subscreen by changing opacity from COVER to TRANSP.