Hi, @Christina070, homework questions are a special subject here. People avoid giving direct answers but may help guide you towards an answer.
In that spirit, here are MY questions about Afghanistan. I can’t answer any (seriously I have no idea), but following them might help you.
Did the US congress authorize the current war? There would have to be a bill passed by Congress and signed by the President.
Was there a UN resolution authorizing the ousting of the Taliban in 2001?
When the US and NATO kicked out the Afghan government, what was the replacement? Is there a constitution?
Hope that helps. And I for one would like to hear about what you find, if you have the time to post it back here.