I recently puchased all the game add ons but when I go to downloadable content their all their but not installed. Does anybody have a clue how to install them please thx

Not sure if I completely understand what you mean but the best thing to do is download again, you won't need to pay again.

At the main menu about 3 down from new or continue game is downloadable content and when i go in to it all the add ons r there but they say there not installed when i check each one have u bought any add ons

Hmm I htink I remember coming across this too.

I'm pretty sure you have to update the game somehow, try turning the game off and on, failing that go to the add-on in your memory settings, there might be an install option.