looked
v.v. to direct your eyes toward something so you can see it. You use this when you want to describe someone's appearance or how they seem to be.
v. to direct one's gaze in a specified direction; to have a particular appearance or to seem to be in a certain state. Often functions as a linking verb followed by an adjective.
She looked at the map to find the way.
The manager looked tired after the long meeting but stayed to answer every question.
He looked across the valley, noting how the shifting light transformed the rugged landscape into a tapestry of deep purples and golds.
When used to mean 'directing one's gaze', it requires the preposition 'at' before an object. As a linking verb, it is followed directly by an adjective rather than an adverb.
She looks happilyShe looks happyWhen 'look' describes someone's appearance, it is a linking verb and must be followed by an adjective, not an adverb.