Need help with particle effects in game

can anyone explain me how to make particle effects or better rendering in game?
Like to see sun lights coming trough window like this : https://www.google.rs/search?q=unreal+engine+4+particle+effects&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi49t214-rSAhXLnRoKHT-2DkcQ_AUIBigB&biw=1366&bih=638#tbm=isch&q=unreal+engine+4+sun+&*&imgrc=3BSdpml9voOXTM:
And how to make it indors?

After that how to add reflection to metal textures or tiles and water? Such as this - https://www.google.rs/search?q=unreal+engine+4+reflection&hl=sr&site=webhp&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiUhfmR5OrSAhUFbBoKHTRZCX4Q_AUIBigB&biw=1366&bih=638#imgrc=8rHXicKy79AJWM:

If anyone knows how to do this stuff it would be nice to hear that!