Auxillary verb have and Verb have

He still had not the courage to approach her。
Do you think it is a good sentence.I am not sure the basic use of auxillary verb have and the verb have. Are there any rules?
He still didn’t have the courage to approach her. ----> is better for me.
He still had no courage to appraoch her. ---->It seems okay for me.
Any idea?

He still had not the courage to approach her。Do you think it is a good sentence.-- It is good grammar but literary in tone.

I am not sure the basic use of auxiliary verb have and the verb have. Are there any rules?-- Please be more specific — what kind of rules are you expecting?

He still didn’t have the courage to approach her. - This is the standard conversational form.
He still had no courage to approach her. –This is fine, too. A little more formal.