hi there :) if I got it correctly, you’re looking for the webtoon with the storyline you’ve described, right?
if that’s the case, the webtoon you’re looking for is most likely “The Evil Lady's Hero”.
Is not a webtoon but a novel, however is exactly what you are looking for and is soooo good, the name is "I raised a black dragon", give it a chance, you are not going to regret it :)
Most of reincarnated/shoujo manhwa are plotted like that actually.
When I first got into this type of mahwa I have this website as a guide. Feel free to check.
https://www.listchallenges.com/isekai-mangamanhwa-with-strong-female-leads
Does anyone have any recommendations oh manhwas/mahuas/manga/webtoons that the MC id the Villainess that's gonna die in the near future but someone from the present time got reincarnated into the Villainess' Body and is determined to change her fate by breaking up or doing anything she can in her power to not lead her to being executed/killed pls help i'm desperate