I think it's an one shot about two twin sister falls in love with same guy..but the guy loves the older one and they were making plans to get married..and while shopping to propose for the older one with the younger one he gets into accident while saving her..and I think he becomes blind..and kind of blames the younger one..but the older one leaves him and the younger one takes care of him by acting as the older twin...but somehow he recovers and the younger one returns her place to the older twin to get married as planned..and somehow he finds out in the end..and yeah happy ending....please help me find the name of this one 😢 😢

Perhaps you might be talking about this? https://www.mangaupdates.com/series.html?id=12093 It's a collection of oneshots and your description matches the third story which is ''The Flower that Blooms in You by Mitsuya Omi''.

Anyway I too am looking for a manga if you could please take a look and let me know if you know anything from my shitty description would be a great help https://www.mangaupdates.com/showtopic.php?tid=122314

Thank you sooo much... it's the one I was looking for

I don't think I have ever read the manga you described about..but I will try to look out for you 😁