Many birds travel hundreds of miles during seasonal migration, so having a way to successfully navigate the journey is essential to their survival. Although flyways provide a general outline of the routes taken by migrating birds, new visualizations like the Bird Migration Explorer highlight the unique pathway and challenges each species faces during migration.
How birds navigate has been studied by scientists for many years and evidence has accumulated about birds' ability to create navigational maps. These maps are created using a variety of tools which may include a specialized magnetic compass that relies on light receptors in the eye, or a star compass for birds that travel at night. While this map-making ability appears to be innate, experienced individuals also use what they learn during the journey to aid future trips. You can read more here about foundational studies on bird navigation and the tools other animals use to navigate.