This has been answered in another thread with very thorough documentation on how it was achieved Changing Materials with UMG
The same concept can be applied to modifying anything you want about any actor in a scene.
I got the colour change script but unable to communicate with the bp actor or the sofa I want to hide one sofa when the other sofa is visible with the button click…how to get the reference from the bp actor to the widget and set the visibility on and off on press of the button.
If you follow that tutorial, you will have a reference to the “sofa” actor. You can then use that reference to do whatever you want with it. You can apply a rotation, hide it, change its material …
in place of sofa I used two different shapes as bp actor class the I used variable as static mesh actor and added it but still they are visible .i added a print string to see that the connection flows …and yes it works
You did not follow step 1 … you did not give your references to your widgets. Notice how after the widget is created, cone reference is passed to it.
Like I said, everything you need is right there 
finally got it thanks for giving me the hint I am new to unreal engine … thanks for the reply… it means a lot to Me I am working on it from a long time… thanks…
changing the material is over changing the mesh i got it but when i change the mesh the buttons are not updating the materia tothe next modle.