WARNING: I am not an expert.
With a synopsis you want to engage emotionally in order to create interest, It doesn't have make the reader feel a strong a emotion (bonus points if you can do that) but using "/name here/" feels non-comittal which makes me disconnect from the story a bit.
I think there are some other challenges to overcome with this synopsis as well. "...kingdom in a single day falls..." feels like awkward word placement to me.
"...he must teach a blind girl the ways of magic to restore himself"? Huh? This feels a bit random. So not only does he know magic but he knows it well enough to teach it to a blind girl. Why would would his teaching it to this specific girl be beneficial to him? Things just feel disjointed in this synopsis like there's an aspect of the story you're hiding. Don't hide any part of the premise, that's what will convince people to read the work or get interested in the work.
Here's a rewrite (I've take some artistic liberties and added some stuff just for the example):
The crown prince of the /name here/ kingdom in a single day falls after losing his most precious power- Control. Now hunted by noblemen and commoners alike, he must teach a blind girl the ways of magic to restore himself and if he fails he will lose the thing he holds most dear - his freedom.
When a mage-prince's kingdom and power are ripped from him by an infamous bounty hunter's curse he is forced to flee, set upon by his own subjects. Now he must teach what magic he has left to a girl who was blinded by the same bounty hunter. He has the wisdom, she has the potential, and together they can perform a spell to find the source of all his troubles and end both their curses before the end of winter.
Who is he and what can he do? "When a mage-prince's..."
What's the inciting incident? "...kingdom and power are ripped from him..."
Who's the villain (if applicable)? "...infamous bounty hunter's..."
What's the main goal of the character going to be? "Now he must teach what magic he has left to a girl who was blinded by the same bounty hunter."
Why that girl? They were cursed by the same guy! Which links them and helps the audience to accept them working together and possibly becoming fast friends.
Here's another thing that links them: "...and together they can perform a spell to find the source of all his troubles and end both their curses before the end of winter."
Why before the end of winter? Well this is a great way to allude to something terrible happening with their curses at the end of winter and also a great way to create a Ticking Clock within your narrative. When characters you care about have a limited time to complete something or solve a problem, this creates tension; make sure to establish stakes/ what's at risk before establishing a time limit.
You don't have to accept the rewrite but I hope it gets you thinking about just how much you need to be communicating with even the short synopsis.