Not too bad first chapter. Here are some notes for you. Remember these are my opinions:
1. The pacing in chapter one is too fast. We get half the chapter in the real world and half in the fantasy. Neither is fully developed. Slow down the individual scenes and expand on them. focus on establishing your main characters.
2. Don't write the number 2 instead of the word to. It's incorrect grammar.
3.Explain more what the setting looks like. not enough details about the environment.
4.If multiple suicides happened at the school, the roof would absolutely be locked to students.
5.I question why Hikaru is at school at all? He should be in a mental facility somewhere for multiple suicide attempts.
6.Describe what Hikaru and Hana look like please.