Is God angered by children who forsake their father who was negligent in raising them and mistreated them, knowing that he does not pray?

Your father abandoning prayer is one of the greatest evils, because it is disbelief that expels one from Islam. You must advise him and not despair of his repentance, using various means such as audio recordings and seeking help from those who can advise him. You must treat him with kindness and dutifulness, even if he mistreats you, just as Allah Almighty commanded kindness to parents even if they strive to make you associate partners with Him. Turning away from him will only worsen his condition, and your kindness to him will not be lost with Allah.