I Disguise Myself as a Man and Serve as an Official in the Court

Looking for a Girl to Dress up as a Boy and Have a Few Close Friends Who Are the Sons of Aristocratic Families.

(Preferably fantasy-oriented) A woman disguises herself as a man, has a noble son as a friend and teammate, admires and protects the heroine, and the group dotes on the heroine. The heroine is very strong and repays her friends with sincerity.