Well basically it's not the adaptation of to be or not to be, but it has some similarities considering how the mL in both series and manhua are prince of a country.
The ml of the series didn't know he was related to the king. He was an undercover spy who fell for the mc (7th prince who was all about poetry, art and 1 instrument which is the same as Lan zhan). So basically the MC is not fit to be King because he doesn't know anything about politics, similiar to, to be or not to be.
BUT the ML in kill to love is quite a red flag. I won't spoil you but he's like "I will let the world burn just to have you". (Similarly happened in the series too)
The series is good!
Oh, I watched this from bilibīli, it's a Chinese app banned in my country but the servers are available. Keeping that aside, it was removed from the app so as of now I'm not really sure which platform will have it.
I think telegram might have it or daily motion.
(I only know illegal sites because it's Chinese bL series we talking about, can't find them anywhere else sometimes.)
Officially Viki/viu had them. Unofficially try kisskh. But it's free on yt. ---- https://youtube.com/playlist?list=PLhd4wr2gniAIyI4nj00zP9hz_PNnJ41Fn&si=igWtNFygteJ8JuAk

https://www.mangago.zone/read-manga/to_be_or_not_to_be/
This reminds of love hate. The chinese bL series.
(They're not the samee but some things and plots)