What is the ruling on things a father brings home from his work, knowing that they are impermissible, and what is the ruling on using these things out of necessity?

It is unlawful for your father to take the employer's money without the employer's permission. You should advise him to return what he took to its owner. If he does not know the owner, he should give it away in charity. As for you, it is not permissible for you to use this money except in cases of necessity.