BALNIBARI
Balnibarbi is the country Gulliver visited in the fourth part of the book, where he studied the life and customs of the land and encountered the problem of the immortality of the struldbrugs. Balnibarbi is absent from the novel "Gulliver's Travels." You may be confusing it with Laputa, which Gulliver visited.
An encounter with court etiquette: In the capital of Laputa, which turned out to be a country located on a floating island, Gulliver had to "lick the dust at the foot" of the king's throne. He was lucky, as the king liked his stories, and he lived at court for three months.
Realizing Illusions: Gulliver was offered a place at court, but he decided to leave, disappointed with his journey. He saw that Laputa was not the land he had dreamed of, and that even the wisest people could have an unhappy future.
Meeting the Struldbrugs: In Laputa, he met the Struldbrugs—immortal people who were doomed to eternal old age. This showed him that immortality was actually a curse, not a blessing.
Awareness of Injustice: The encounter with the struldbrugs made him think about the injustice and cruelty of the world, where even the kindest people can be doomed to suffering.
Realizing His Life: After this trip, Gulliver began to reflect on his own life and how he had lived before. He realized that all his previous aspirations had been futile, and that he had wasted his life searching for unrealistic ideals.