No, you would say - good behaviour and the adjective is well-behaved.
The noun behavior has the adjective form behavioral. (The UK spelling is behavioural.)
behavioral
"Exemplary" is an adjective that can describe behavior.
As a verb, "explaining behavior" is the act of using words to explain a behavior. As an adjective, "explaining behavior" is the observable behavior in which a person tends to explain her/himself.
Fearless is an adjective because it is a descriptive word.
The word well is an adjective, for example well water or well wisher.
annoying, obvious, nosy
Yes, anyone can exhibit acrimonious behavior. Acrimonious behavior is characterized by bitterness and harshness in interactions with others, which can be displayed by anyone regardless of age, gender, or background.
The adjective "mannered" means polite or showing a particular behavior.
Well, an adjective for bee is 'bumble.'
It is well with you
The word wanton is an adjective; a word to describe a noun as causing harm or damage for no reason (wanton behavior, wanton destruction).