It’s in the WEBTOON app and it’s free
there is no complete translation of the novel but if you just search it on google wthere is alot of sites. but they lack the last chapters
https://www.novelupdates.com/series/remarried-empress/
not yet done being translated though. It has only until chapter 195. Can't find a complete one. Sorry.
Like the comments Above me said, it’s not completely translated anywhere. I read it on Naiver, it’s complete there.
*naver
does anyone know where can i read the novel? which is the completed one