
So Idk why, but I'm 70% sure that it's a webtoon/manhwa, but the rest 30% says it's a novel
So what I remember is:
A girl has reincarnated into another world, as a little girl, where there's magic(so fantasy), and she's engaged or married to the male lead and she takes care of him, and one thing I distinctively remember is that the girl at the age around 10-14 she makes medicine and she creates for the first time in that world, a medicine in a form of a pill and tests it on the knights and then sells it to another kingdom for profits.
I remember more details but that's the main gist of it, I think

I don't know what one you're looking for but there's some similar like 'Who made me a princess' where the mc gets reincarnated as a little girl in a fantasy world and there's also 'doctor elise' where the mc was a doctor and got reincarnated as a noblewoman and works as a doctor in a fantasy like world

I found it! AFTER MORE THAN HALF A YEAR! It was actually a novel called 'I'm ready for divorce' Thanx again! https://www.novelupdates.com/series/im-ready-for-divorce/?pg=6#myTable
It's about the fl going back in time i think and she's facing her sister who steals first her childhood crush then her boyfriend then her fiancee and the sister has a bracelet that lets her see the percentages of the love interest and she can manipulate them. And I remember the fl is doing a perfume business and her sister tried to set on fire the perfume creator so that she can overthrow her business
dump fire sister. Wanna read this badd
Exactly bc it's that bad I wanna find it(▰˘◡˘▰)
i believe what yall r looking for is "i stole the heroine's first love" :)
https://www.mangago.zone/read-manga/i_stole_the_heroine_s_first_love/
YESSSSS THANK YOUUUU!
Thank youuu