
So who is the real ml? I’m getting confused ;(

It's still not clear..plus no spoilers as well..if you read the author's other webtoon..the FL ends up with the close friend..
So the close friend in that webtoon has white hair and looks like Chris from this webtoon..
While the best friend in this webtoon is the black haired guy..
One thing for sure she will definitely not end up with shardin..he's feelings are not at all sincere.. ┑( ̄Д  ̄)┍

Okay so I’m at chapter 2 and I already saw that Serenia girl and I don’t really like when the ml likes someone else so please spoil me before I continue reading ;( who is that Serenia girl are they together?

She is a reincarnator to if im not mistaken. Pardon me if Im wrong since it've been a long time I read that part. And worry not my friend, serenia and the ml is just in a kinda teacher and student relationship . Serenia taught him swordmanship again if im not wrong. And they are definitely not interested on each other.

So is the ml the crown prince? Did he love our FL?

Yes, the ML is the Crown Prince. Their current-time relationship halfway resembles The Villainess Reverses the Hourglass (ie, he treats our lady with respect).
As for spoilers (about their relationship in the previous timeline)
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He loved her even in the previous timeline, but had to pretend he didn't to protect himself from his enemies (such as the Duke/fake dad). He knew from before they got married that she wasn't really the Duke's daughter (whom he hated), but he wasn't able to ask her who she really was, and she wasn't aware that he figured it out. So the love of his life died without his ever learning her name...
In the novel, he does manage to get his son back from the Duke and the real Veronica, and tell him all about who his real mother was as a person. No idea if he was able to raise his son to adulthood, though, with the Duke being...well, the Duke.

No, they're currently only feels like a close friend and then married for the best of their country (to weaken the duke's influence). In this timeline, she continuously rejects his proposal to be his empress but maybe in the past timeline she later agreed out of conscience. The crown prince's true love is Elena only both in this timeline and the previous ones
I HATE THE PRINCE Y’ALL. AND I HATE HOW THE “heroine” ALWAYS CRIES LIKE STFU BIATCH TFFFFFFFFFFFFFF I HOPE THEY DONT END UP TOGETHER GRRRRRRRRRRRR
sorry didn't mean to downvote༎‿༎
RIGHT?? I found the so called “heroine” was annoying as fvck