Move WP from 1&1 hosting to cPanel host.

When I tried moving a wordpress install from 1&1 to bluehost with cPanel I kept getting an error on bluehost saying:

Fatal error: Call to undefined function wp() in /home2/tilearti/public_html/test/wp-blog-header.php on line 14

I was using the Duplicator plugin to make a backup of the db, and using ftp to copy all the files…

Now, since that wasn’t working, Any other suggestions or help would be wonderful!

Thank you all!