It is forbidden to work for commercial and conventional banks as they base their profit on usury and Riba, which is one of the major sins in Islam.
Islamic banks don’t lend people money. They sell things to people in installments or they share with them in a business.
If they lend people money with interest, they are not Islamic anymore.

Please i want to know the rulling of working in banks. Some schoolars say its forbidden because banks make their money through profits, others say even islamic banks do the same.