HTML / CSS - Open local HTML page

I'm making pack of Chrome Extensions, kinda life hacks for Chrome for school. I'd like when I open up E-Diary to load custom local .html file from a PC (that will be in extension folder). So for example, I'm on page www.test.com and instead of showing real test.com I'd like to show .html file of test.com but with changed some values (texts, words...) FOR EXAMPLE PICTURES: - Before (real website): http://ift.tt/2n0NC7H After (local .html file): http://ift.tt/2zCCa8h

In manifest.json I have only this:

{
  "manifest_version": 2,

  "name": "Custom HTML Loader",
  "version": "1.0",
  "description": "HTML",
}

I have no idea how to start, there is no simular code to what I want.