Is it obligatory to leave work immediately, or after finding an alternative, if the job requires printing prohibited materials such as cinema advertisements and assisting in the establishment of an interest-based bank, taking into consideration the employee's health conditions and his ownership of a car valued at 30,0 riyals?

Printing or writing about prohibited cinema and usurious banks is forbidden, as it falls under aiding in sin and aggression. You must either continue working on the condition that you do not accept printing or writing anything that is forbidden, or leave it and seek another job. Whoever abandons something for the sake of Allah, Allah will compensate him with something better. As for necessity ( اضطرار ), it is when a person reaches a state where if he does not engage in the forbidden, he will perish or come close to perishing. So, if you are compelled to do this work for your daily sustenance and have no other source, then remain in it until you find a permissible alternative, while diligently searching for one. If you have another source, then you are not compelled, and it is not permissible for you to continue working in what is forbidden.