How serious is surgery on the carotid artery?

My dad needs this surgery and is telling me it's not that serious. My parents don't have a lot of money, and neither do I. A plane ticket will cost me about $400 and I barely have it, an am about to lose my job. But I want to be there for my dad if this is really serious. Does anyone have a sense of how serious this is? He is telling me to save my money in case of bigger health problems in the future, but I'm afraid he is just downplaying the seriousness of his situation. Also I think my mom could use my emotional support since she is alone with him.