These fees vary depending on the airline. You can check whether luggage is included in your ticket by going to the airline's website → Manage booking (or Your trip), the name varies from airline to airline → enter your Trip with your booking details. There you can check the baggage rules.
If you purchased your ticket inside our app (when you specify your address, etc.), you can check the details in the Flight Order widget. See the following screens:
1. Open the Flight Feed and expand the Flight Order widget
2. Click on "Manage" to check the information about the purchased details.
3. Scroll down for direct links to reservation management and airline FAQs.