( @useracasoo ) — i know exactly how you feel !! it might sound insane but one way i was able to figure out how to keep unpredictable going was constantly dreaming about it lol. i would dream of different scenarios from the chapter i finished writing until i thought of the one i liked and would replay it in my head so i could remember it in the morning. when i would wake i then knew the basis of what the next chapter would be about and go off from that (hopefully that makes sense). i lowkey made myself obsessed with the story to the point that i couldn't read any other fics or write anything else if it wasn't unpredictable, so i would and could only focus on that. maybe that might work for you too?
i also struggle with having so many ideas and not knowing where to include them and how that i just begin to write and hope that in the midst of it i can tie in one of my ideas. if i can't then i will edit the chapter later to include it or add it to another chapter. or, if anything, i will save the idea and add it to another story. i hope this helps or make sense. explaining my writing process really makes me question myself lol
also !! don't let any of that discourage you! everyone is made to write, including you ! all you need is to just go for it, and once that first part is published, you'll figure out along the way what works best for your story and what doesn't. don't be disappointed if a chapter doesn't go the way you want it to, you can always edit that later (or keep it and work around it). the most important thing is that you finish it and keep on writing. of course, don't burn yourself out ! don't be afraid to take your time in writing, i sure did !
i wish you the best of luck in your writing !! and i hope that my advice may help, even if just a little bit <3