packing my bag for my trip

I am going to start my trip on next week. So i have to packing my bag!
First, i have to bring my passport. Because i have to go to other country, but if i don't have passport, then i can't go. and i have to buy a big bag which has a sleeping bag. because i am student and i dan't have enough money for hotel. i think there might be many time that i have to sleep in the train or out side. and i have to bring some medicine. because if i am sick in the other country, there country's medicine is not fitting on me. because the medicine that in the other country is made to fit their country's person. and i have to reserve the airplain seat. and i have to bring winter clothes and summer clothes. and i have to bring my camera for take a picture for memory. and i have to bring money. and i need guide book and language book for each country. and i have to tell my mom and dad that i am leaving! there are so many thinhs that i have to do........T.T