Create index.php

even if i don't know how to start this but
i have a host, free host (cause i can't afford a paid host)
they give me 1500 GM with PHP , MySQL , limited Apache
so i will build it using third party plug'ins

the idea here is to create a website that help "LEARNERS"
(actually anybody) to learn (anything).

i need a framework for:

 Lessons & Tutorials creating & viewing
 Exercises creating & viewing
 School like social networking
 Relations teacher-student & student-student & teacher-teacher
 users accounts & profiles
 etc...

it's kind of blury now :(