Marketplace to the rescue, some widgets I found for you;
https://marketplace.mendix.com/link/component/219410
Hello Abrar,
The easiest way to do this, is by creating an on click action nanoflow or microflow that turn a boolean(show layover) on or off.
If this boolean is on then you show with conditional visibility the layover if this boolean is off you do not show the layover.
For your layover to 'pop out' and to not affect the other functionaility you need some css probably you need to use something like position: absolute or position: fixed and maybe you also need to create some shadow.
Hope this helps!
Good luck