Is what the father is doing – taking assistance from the state, despite knowing he is not entitled to it, and stopping repayment of loan installments to save money, and deceiving the lawyer – forbidden (haram)? And are food and drink in his house forbidden (haram), and is his money forbidden (haram)?

It is not permissible to take conditional aid that requires not working, with lying and deception, nor is it permissible to take an interest-based loan except out of a recognized necessity, nor to place money in interest-based banks and benefit from their interest. Lying and cheating are forbidden. As for eating from the food of your father, who works and has permissible income, and his money is mixed, there is no harm in it according to the preponderant opinion. You must honor him and be gentle in advising him to avoid forbidden acts.