What is the law if you have to join an interest-bearing transaction for the survival of the company?

My father has a halal business but involves riba,that is he has a loan where he pays interest.He now ask me to help him in his business.If I help him ,I will have to pay interest ,also will have to witness many transactions of interest. How can I be dutiful to the parent in this situation?How should I help him in his business?Also ,the loan amount is so high that it's repayment is not possible inorder to make it halal and the only way to avoid the bank attachment is by paying the interest for lifetime. Secondly After his period ,in future, as a son I will be liable to pay the interest and loan to avoid bank attachment. Also I have warned him about riba and have not helped him in taking any kind of loan. ..Pls help.....

It is completely wrong that your father took loan from Bank. but the amount your father took as loan or the business which he had done with that money is not haram because that is not interest.

On the other hand, if anyone take money as a loan and payback this money with interest his activity will be haram and his money will be halal and if anyone give to someone money as credit and take interest so his activity and interest amount also will be haram.

even though in this situation where you have to complete the debt with interest you may help your father and be a part in his business...