These words describe an amount of money that needs to be paid - but they're used in different situations.
Fare is used only for transportation:
The bus fare is the cost of the bus ticket
The train fare is the cost of the train ticket
The taxi fare is the cost of taking a taxi
Airfare is the cost of a plane ticket Fee can describe:
The money charged for some professional service. You pay a fee for
lawyers, counselors, maids, etc.
The money charged by an institution or for administration:
Schools charge tuition fees.
When you do something official like get a driver's license or register a marriage, you may need to pay an administrative fee for the paperwork to be processed.
When you apply to colleges or schools, you often have to pay an application fee.
The word tax refers to the money you need to pay the government. Most countries have an income tax - meaning a part of your salary is paid to the government. Tax money helps pay for public projects and infrastructure.