Question

一体化の子

hey I have some questions about Japanese school life , which won't take up much of the time, plz help me!^_^
1.Is 漢文 a serious subject among all the subjects?if I'm bad at that will it badly affect my college extrance exams ?

2.is it possible and polite to talk to Japanese in English during school time ?or maybe in all 漢字(伪中国语)?is there any basic rules about 伪中国语？

3.should I bow in 90°to all my classmates ?when is it ok to stop ?and......is it true that Japanese ppl r usually a bit cold to foreigners(usually ppl from my country )?(no offence)