Thank you so much! Glad you liked the story :D
Well, it's my first narrative game and I know what you're talking about not knowing what system to use, I've been there. So everything I'll say is about the experience I learned from it, so I'm not an expert ahahahaha.
For the dialogs, I use .csv files; one column is for the key of the specific dialog I want (I also use it to know which character is talking), other column is for the text, and for this game I used also a third column called "Action" that says if the code has to read the next part of the dialog or close it. Something like this:
| Key | Text | Action |
| Mom_firstScene | Good morning sweetie! | Next |
| Someone has slept in uh ;) | Next | |
| I told you not to stay up watching that A Regular Tv Show so late | Close |
For each scene, honestly I coded all of them from scratch ahahahaahhaha. Not the best way but since there weren't many scenes and I didn't have much time to make something more sophisticated I used this method. For example you can use the Animation system your engine has, but I don't like it too much; you can use .csv files making a scipt parser and making your own system (not recommended, it's poorly redeable); or I'm sure there are some other more efficient methods to make them; even maybe your engine has some community-made plugins to do it. For example, in a game I'm currently making I'm making a visual node cinematic system for myself that I think would allow me to make scenes like the ones I made for this game easier and faster.
And about how to structure the narrative... Well, I also struggled a bit on some parts but I think something that works is asking yourself what would you like to happen after every point of the story. Like thinking of yourself as a player, what would you like to see? or what would you like to happen on the game? Is like making the story you'd want to see. If something is funny for you (or whatever the feeling you want to transmit) then it's good. I don't know if I'm explaining well, sorry ahhahahaha. To give you an example of this game; I needed an excuse to make the player go to the abandoned house for the first time, so I thought of some ways I could make it and the one that liked me the most was "someone calling for help", because I thought on the washing machine thing and I found it funny, so I said: "Okay, someone calls for help, Billy runs away and when you enter the house you found Master stuck inside the washing machine. I like it".
I don't know if I've explained myself well on every topic, I hope so.
I hope you find this useful! :D