Update of existing wordpress website through a new theme that needs customisation

All the details have already been discussed with a Freelancer. We would like to keep all the coding on www.buildmyskitrip.com, however use a more interactive modern theme for Wordpress to make the site more modern, faster and attractive. It is hosted through Go Daddy and we would like the Freelancer to customise the site in the same way as the current website, however we need to input new information as some of the current pages are vacant of this information. We would also like it linked with social media.