Hi Chandan Kumar, 

Thank you so much for your question. If you want to change the title of the page, you can do it in the main editing area of the Page Editor. You can also change the permalink, which is the end of the URL, by editing the permalink settings in the right-hand panel while in the Page Editor if you're using Gutenberg, or above the main title area if using the classic editor. 

Kindest regards,