Change website files from .php with to .html

Freelancers - I need your help, please. I need changes made to a new 4 page "responsive" website design. The "responsive" part of this new site functions well. The design company I hired to re-design my old site not only made my old site responsive, which was great, they took it upon themselves to completely change all of my .html files/pages to .php files/pages. Because of server/software issues I can't use .php files or the corresponding bootstrap files that they sent me. The design company I used has already been paid and they won't answer my emails to solve the problem they created. I'm looking for a very experienced web site designer that has thorough knowledge with all types of coding issues. I need this new responsive website, its pages (.php), headers (.php), footers (.php) along with the css, javascript, bootstrap to be changed so that all of the files are compatible with .html files. I do not want .php files or bootstrap on my site because of my server. This requires changing the coding. The 4 web pages I have need to be renamed .html and I need all files associated within the website to work with those .html named pages. This job does not require just re-naming the pages to .html it requires that you remove all of the bootstrap and fix the javascript, css etc to work with web pages named [login to view URL] extensions. Until I have .html files/pages to work with I can't even fix their design work and trust me it needs changing. Make sure you can understand and can complete this project before bidding. If you need to ask questions, please do so before bidding. Website files will be provided via zip file. Thanks for taking the time to read my special request, it's appreciated.