Want to merge two scene a person talking with the background of jungle but should look as if the scene is taken in jungle

What you’re asking to do here, at face value, some advanced composting and special effects work. You didn’t mention what exactly is the person talking footage. If it’s green screen your chances are a lot better, but if not, your chances are not very good. You can try Premiere’s new Object Mask tool as the easiet method. Other than that, you’re into some more advanced compositing and rotoscoping. Assuming the footage is good. If the footage is bad, a reshoot is probably in order.