I go to Japanese weekend school every Saturdays to chachstay caught up with Japanese secondary school 's study pace.

If I wouldidn't go to there, I would get in trouble when I went back to Japan.

I learn mathematics and Japanese at athe school.

You should say "the" here as you have already introduced the specific school you are talking about

hHowabever, today was special because our school is having graduation next week.

sSo, I got to go home earlier than normal saturday.

I got home --> I arrived home
I got to go home --> I was allowed to leave

And we practiced ofur graduation.

It is common to graduatione is somewhere around the first week of March or second week by the wayof March.

To + word implies a verb, so here it would be "to graduate". Graduation is a noun.

ItThere is a difrference of when graduation is , between foreign countries and Japan.

Any way, I am wondering that which one is the correct sentence, 「: "my backpack was broken" 」or 「"my backpack broke".」

We never use「」in English, only "".

Both of these sentences are correct, and both are in the simple past tense. "My backpack was broken" is also in the passive voice.

wWhen stuff broke,eaks, native English speakers says 〇〇it is broken , so I am so confused.

Present tense here --> when things break.

I found some websites explaining it better than I could
https://proofreading.ie/portfolio/using-broke-and-broken-correctly/
https://www.grammarflex.com/knowledgebase/broke-or-broken

If you could reply agensthave an answer to this question, please write for melet me know.

This is a more natural way to phrase this sentence

It help so muchwould be very helpful for me.

OR: It would help me so much.