Is the fiancé entitled to prevent his fiancée from working after marriage, despite her father’s condition that she continues to work after marriage, and what should he do about that?

There is no harm in a girl working if she adheres to the Sharia (definition) guidelines. A husband has the right to prevent his wife from working after marriage, unless she stipulated working in the marriage contract, in which case he must fulfill the condition. If the girl agrees to leave work after marriage, there is no harm in her father's condition, but it is better to try to convince her father to drop the condition. The husband should help his wife in honoring her father.