WordPress and Server Admin Expert Needed

I need an expert in both WordPress and server administration to review my entire high-volume website. The site has not been updated with the latest WordPress, PHP versions, or plugins. The task involves assessing the current state and implementing necessary updates to ensure security and performance. Experience with cPanel and MySQL is essential. I need someone who writes and reads good English since I expect we will need to talk about what is found and what changes are needed. The most important point is that the site needs to remain functional and any major change needs to be tested on a copy of the site or server before the live site is changed.