@HabibUrrehman,
I have a brother who's come to believe in 9-11 as an inside job. I do notice that 9-11 conspiracy theorists, and I have no particular buy in one way or another if it's true or not, never deal with the operational requirements of such an event (being an inside job), nor the motivations of each of the U.S citizens who would have had to participate - each having intent to mass murder <and each knowing they would be killed afterwards to keep them quiet>, nor with the willingness of particular attackers to die. (Reminder - this is from the point of view that it was an inside job - the questions that need to be asked). When I run through the permutations of this - I cannot see it ever happening.
Compare that to the official version of hijackers, and the operational ability and motivation is there. It's confirmed in prior history and in events to this day. The version of how it unfolded is also credible.
That aside - one of the most interesting aspects of the collapse, was where did all the steel girders go? Not even conspiracy theorists explain this particularly well. It appears to me, that if they (the twin towers) collapsed on themselves, that at least the girders above the strike site should have survived intact, with the concrete falling down in between it. But this isn't the case.
I'm not surprised by the suspicion of controlled demolition. But at this stage, having read a fair bit on it, and not being able to find satisfactory answers
relating to operational requirements and motivation - I still don't think it is the case - that of course, is an opinion only.