The game has such strong potential! I deeply enjoyed playing through it and love the characterization of Finn and Jack, their designs are aesthetically pleasing, and the plot itself is genuinely interesting.
Aside from a few very minor grammatical errors, my main piece of feedback would be to look out for moments where the narration repeats the same idea twice. It's not anything major, but tightening a few lines can make the writing feel smoother and more impactful.
For example: “Maya only gave me that short explanation and left. Everything was explained to me very briefly, but I took it as an opportunity.”
Both sentences already communicate that her explanation was brief, so it can be combined into something like...
"Maya left without a glance back at me. The explanation was brief and vague, but I took it as an opportunity."
The emergency button scene was also a really nice touch! Rather than cutting information, I think it could be even more effective if some of the lines were rearranged to build suspense around the discovery.
For example: "I scanned the item more closely and noticed writing on it. I almost dropped it out of shock—I recognized that handwriting. It's *Amber's*. 'In case of emergency, press this button'"
For the part where the MC hides the button, that can potentially be condensed as well, such as...
"To avoid suspicion, I hid the button in my pocket to inspect later. I couldn't risk letting anyone find this and taking it away."
It, again, falls back to trimming small bits of padding or repetition. Nothing about it is awful by any means! The writing already has a solid foundation, but a little tightening here and there can make the emotional and suspenseful moments hit HARDER.
My last point I'd say to take with a grain of salt, because it's more of a personal preference. I LOVE descriptive writing, and I'd enjoy seeing a little more description of how characters sound before they speak. We can already see their appearances through the sprites, but their voices are left to the player's imagination!
Jack, for example, has a low voice. Is it gravelly? Smooth? Rough? Adding that little bit can help players picture him more clearly.
For example: "He spoke in a voice that's low, rough, but cordial. The kind of voice you'd expect from someone working in the military."
Overall, I love the premise you have here, and I'm BEYOND impressed that you made this all on your own (aside from some help with coding). I'm excited to see where the story goes and what future updates bring!
(I also hope this is easy to read. I understand English isn't your native language, so hopefully the translator can have mercy and convey what I'm saying.)