I have a project in which I want to merge two wp themes, I have two themes in which one has a great interface i want to use this interface and second theme has a good functionality so I want to use that fuctionality with first theme, but I have no idea about this, can it be possible??? if yes how can I achieve this provide some refrence.
Milo is correct, it is a very broad question. That said, what you want to do is totally doable, BUT, it is going to take effort.
There is no easy way in mergin two themes into one. You will have to set up a completely new theme, and then you have to start to extract every little piece of code from these two themes, add it into your new theme and integrate them them to work in harmony.
There is unfortunatly no other quicker way of doing it that I know off or came across. Make yourself ready for a bumpy ride and enjoy the ride