I feel bad.
I feel (textures) badly. (due to nerve damage in my fingertips)
I am good.
I do well.
I am bad. [subject-pronoun linking-verb adjective]
I do badly. [subject-pronoun action-verb adverb]
I look bad.
I see badly.
She is cheerful.
She works cheerfully.
They are happy; They feel happy.
They do things happily; They cook happily; They read happily. They feel the velvet fabric happily.