The Knight Blooms Behind Castle Walls is a Manga/Manhwa/Manhua in (English/Raw) language, Shounen series, english chapters have been translated and you can read them here. You are reading chapters on ManhwaZ fastest updating comic site. The Summary is
Rosa dreams of taking up arms as a courageous knight! To be one, she must first be a squire. Those duties around the castle are much less glorious. One moment she’s caring for the horses in the stable. Next she’s battling the task of chopping firewood or conquering a mountain of laundry. She must be ever-ready to assist the knight she serves! Her role may seem small and the tasks mundane, but each is an important step to becoming a knight. Rosa will face every challenge with the heart of a hero!