(which make game lite and load fast other than all the questions in form of text file in game).
Not actually true, since you are downloading the content from an external source instead of having already your content contained in your game.
Moreover unless you do have a text file of hundred of megs (and even in this case, this is still quick), text data won't be what makes your game "heavy" or "load slow".
Anyway, to make an actual quiz game, there is a quiz template contained in Construct, you can find it in the Start page in the Templates category.
Then in order to communicate with a distant server, use the AJAX plugin.
You can find examples of implementation in the how do I FAQ for C2, look for "AJAX" in the page.
If you are not familiar with building and maintaining an external server, possibly consider embedding your content directly in the game instead of going the more complicated route of external hosting which possibly has no added advantage.