Going to Japan!

こにちはこんにちは！ 
今月、私は友人と日本に行く。私たちはひこうきで東京に行って、しんかんせんで広島に行って、なごやに行って、京都に行って、おうさかに行く。ホストファミリーはホストファミリーとはなごやであって、私はホストのお姉さんの学校にほもんする。でも、私はホストファミリーホストファミリー宅で５日間だけたいざいする。みじかいね。????
私はホストファミリーのプレセントが買ってあげてわからないよ私はホストファミリーにどんなプレゼントを買っていいのかわからないよ。日本で夏から日本は夏だから、チョコレート (とくに TimTams) を持って来ない持っていけない。たすけてください！

ENGLISH:
Hello!
This month, my friend and I are going to Japan. We are taking the plane to Tokyo, and taking the bullet train to go to Hiroshima, Nagoya, Kyoto and Osaka. I will be meeting my host family in Nagoya, and will be visiting my host sister's school. I will be staying with my host family for only 5 days. Very short isn't it? :(
I don't know what I should buy for my host family gift. And since it will be summer in Japan, I will not be able to bring chocolates.
Please help!

This is my first post, and I know the language is quite basic, and that it is actually quite a short post. It took me quite a while to write as I could only express what I wanted to communicate through the small knowledge I have of the language. Also, I have only JUST learnt plain form. I am unsure of a lot of my sentences, particularly how to say all the places I will be visiting at Japan, sound more 'natural'..? Also, I'm not sure how to say '...and since', and I'm not certain that I have used some particles correctly.

Please feel free to correct me even further. :)

Very good! 日本で楽しんできてください！