stories where the characters have to solve puzzles?
Dreadful night
https://www.mangago.zone/read-manga/majin_tantei_nougami_neuro/
https://www.mangago.zone/read-manga/kiss_the_abyss/This is sooo goood !!
https://www.mangago.zone/read-manga/i_love_your_character/This one too
https://www.mangago.zone/read-manga/sangyang_the_wanderer/
stories where the characters have to solve puzzles?