wow this is a question. wow um. well i actually think in my case it works the other way around; i was always pretty good at writing class essays (at least when i got to college--prior to college i wasn't the best at essays bc i didn't have a solid grasp of writing tbh) so when i joined ficdom i think the transition was made easier bc of my previous writing experience/skill(?). i really don't think i'm the best fic writer or even like. scientific paper writer/essay writer by any means because i still have so much to learn and improve on, but i can say based on personal experience that writing in any form (whether it be for class or fic) is good practice and will feed itself, ie. writing fic helped me write better essays and writing better essays helped me write better fic.

in terms of writing tips: i'd say the best way to improve is to study--by that, i mean to practice writing and to actually digest the stuff you read from the lens of a student. now that i've been getting back into reading fic/ya novels i've been more attentive to the ways that authors use literary devices to paint pictures and develop their plots, which is something i think i am personally lacking in. i have a note in my phone where i jot down phrases/words that i like so that i can refer to it when i'm writing my own fics. i think it's also nice to plot from the very beginning so that you have an idea of who your characters are, what their motivations will be, and what conflict (if any) you'll want to solve (or not) by the end of your story. i'm more of a pantser, which is why... i take so long writing my chaptered stuff... lol. i hope this was helpful! thank u for the question :3