Build a Website

I need a specific set of tasks done to upgrade and stabilize our Wordpress website. We have a current website in Wordpress with a customized theme and a bunch of plugins. The Wordpress version and plugins are out of date and the site needs proper security. The challenge is the customized theme -- which cannot be broken and we don\\\\\\\'t want to change. The site uses php, mySQL, Linux, Google Analytics. There is no cpanel installed on the site host server.\\\r\n\\\r\n\\\r\n\\\r\nThese are the tasks I need completed:\\\r\n\\\r\n\\\r\n\\\r\n1) Create a subdomain [login to view URL]\\\r\n\\\r\n\\\r\n\\\r\n2) Replicate the current Wordpress site in the [login to view URL] subdomain. \\\r\n\\\r\n\\\r\n\\\r\n3) In test environment:\\\r\n\\\r\na. Remove all unused plugins and themes\\\r\n\\\r\nb. Update Wordpress version and plugins\\\r\n\\\r\nc. Install BulletProof Security plugin (I can share settings at the appropriate time)\\\r\n\\\r\nd. Test for functional issues, including desktop and mobile, across all standard devices (desktop, tablet, mobile including IE, Chrome, Firefox, iOS, Android devices and screen sizes) \\\r\n\\\r\ne. Document all functional issues\\\r\n\\\r\ne. Fix specific functional issues as instructed after review with client (some issues may not be important, while others are critical)\\\r\n\\\r\n\\\r\n\\\r\n4) Backup production site and email backup to client. Current site is backed up with a backup plugin -- that backup plugin must be used.\\\r\n\\\r\n\\\r\n\\\r\n5) Copy test site to production\\\r\n\\\r\n\\\r\n\\\r\n6) Document baseline setup for fully functioning Wordpress production site, including Wordpress version, all plugins and settings, theme and settings\\\r\n\\\r\n\\\r\n\\\r\n7) Install cpanel on the site host server if possible (GoDaddy hosting) and ensure it\\\\\\\'s working properly.