Conversion of an existing HTML Page into a Wordpress-Template

Project is containing different parts: 1st: Wordpress is ready for installation on one of our server. It should be done as multi-site-installation, because we finally have two different pages with different content (but both pages will have same layout). 2nd: A Website which is at the moment HTML based (14 single pages, CSS Framework "YAML" used) need to be transformed into a WordPress-Page. For the WordPress-Part need to be used the XTremeOne-Framework (also "YAML" based) as a base. All needed Material will be provided at start of the project. 3rd: There is a second HTML based website with completely different layout. The layout should be dropped and only the content should be placed into the first converted layout, but as a second page (therefore WordPress was installed as multisite-installation) on a second domain. The content which need to be copied into the new layout are only 5 simple pages and a new page which then only contains a download-button for a pdf-