Thank you so much for playing my game and the critique! I'm very new to this genre, so any suggestions and tips are needed so I can improve.
Spoilers ahead for the true/good end:
For the good/true end you need to use the hammer behind the locked box to break the glass bottles. You'll end up collecting a glass shard that can be used to open the envelope. This event will unlock the diary. One of the papers in the room will also become readable and you can unlock a bonus diary entry.
After, you can then use the hammer to break open the wooden box. When the curtains disappear, it means you have the good end event unlocked.
Hope this helps! Thank you again for playing my game and leaving a comment!