Theme copy problem

Hi
I used a theme to make new website and I want to make another website
i want to make a copy from the old website and paste it on the new one
i want all the content from the old website go to the new , and i will modify the content
i tried to copy all the WP files from the old website but when i tried to go to the new one it redirected me to the old one :/
I want you to help me with this and Thanks