How is the world in which we live in can be thought of as a system? ?

Bc everything in it serves as a purpose that makes it run smoothly like spiders eat insects and birds eats sliders and snakes so on and so fourth thus making it a system

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.