What is the ruling on working in a restaurant that serves meals different from what is presented in the display picture, specifically regarding the type of rice, and what is the ruling on the money earned from this work?

Your work in providing meals that involve deception to the buyer, without their knowledge, is assisting in deception and is forbidden, and your earnings from it are likewise. However, if the buyer knows the true composition of the ingredients and is content with them, then your work and earnings are permissible. You must advise the restaurant owner to abandon deception. If he does not respond, then threaten to report him to the authorities. If he persists, then report him.