There are so many like that (lol), but here’s one. His hair isn’t blonde, but it’s lighter than the seme.
https://www.mangago.me/read-manga/ore_no_kirai_na_senpai/
Wait, he really isn’t a prince (more playboy), so this probably isn’t it. Sorry!
Im not quite sure if this is what you're talking about, but from your description, this manhua definitely matches it.
https://www.mangago.me/read-manga/the_royal_prince_s_first_love/ f
Maybe this one. https://www.mangago.me/read-manga/royal_fiance/
I jst realized u were talking about a manga not a manhwa/manhua mb it's not this 1
Not the one i was searching for but im definitely reading this one too!!
i’ve read this one sooooo long ago and I didn’t even finish it back then but it was an enemies to lovers, high schooler? (Or college students but im sure they wore uniforms) one of them was a prince? Or called the prince and he was extremely handsome. He has blonde/light hair if i remember correctly. The other guy was jealous?? And had darker hair (I think, i don’t remember that good.) and it was completely in black/white.
If anyone recognizes it by my bad description please lmk if you want it would be appreciated!!