What do you advise me to do to give up wrongdoing after repentance? Am I sinful for wronging those who do not show their anger, such as insulting brothers without them showing any reaction? And how should repentance be?

Raising one's voice at the mother is an act of disobedience (ʿuqūq), and one can overcome this by making supplication (duʿāʾ) and recalling her sacrifices. Describing one's siblings with bad attributes is impermissible and constitutes slandering a Muslim, which is forbidden. This is considered an act of wickedness (fusūq) and a sin that requires seeking their forgiveness.