i'm right now in the act three so... (SPOILERS)

[hetero bixa]

someone can help me with the quests of each character from the cast for what they need help... if they're totally optional (because i don't know i have to do this for finally beat the the game) to the easyiest one to the hardest one?

[Generic_Bad_Guy]

I don't think they are optional, since learning about them tied into the story. The easiest one is Bonnie, since you can actually just brute force it if you want to. You have to answer 4 questions in a row correctly about what her favorite snacks are - usually you would have to find this out during snack breaks.

For Odile if I remember correctly she is looking for a familytale book, and after talking to the librarian you end up back in the House. I think you had to check the second floor library and/or the secret library in there via the switch to find out who checked it out on a stack of papers, or notice she is checking names of people checking out books. That or some other bookshelf, sorry can't remember! Then you go on a fetch quest with her in town.

For Mirabelle I think you had to notice the papers shes always looking at in town, and get nosy about it. Then if you investigate her nightstand in the 3rd floor dormitory you notice the same papers in there. You may have to talk to her in town again(?), but if not just distract her in the dorm room (I think by checking her bed) and then check the nightstand.

For Isa you don't need to do anything, just do the others first.

[InsaneChaosRealm]

Additionally, bonnie's favourites goes as follows: Rice, Pineapples, Samosas (Samosas without cheese, with potatoes)