Short answers, pulled from the story.
Lake islands emerge from the earth through violent or slow geological processes such as sedimentation build-up, erosion separating landmasses, glacial moraines, earthquakes, meteor impacts, and volcanic activity. These natural forces shape the world's inland archipelagos in countless ways.
Volcano Island in Taal Lake, Luzon, Philippines contains its own crater lake known as Main Crater Lake. This recursive feature makes it one of the few third-order lake-islands in existence.
The Uru people have lived on floating islands in Lake Titicaca for centuries. These natural rafts demonstrate how life adapts to unstable ground in quiet waters.
Modern projects like Flevopolder in Flevoland cover vast areas within the freshwater IJsselmeer lake. Dredging and poldering techniques allow humans to create land where none existed before.
Vozrozhdeniya Island in the Aral Sea grew rapidly from 1960s until mid-2001 before connecting to the mainland. By 2014, what was once an island became part of the extensive Aralkum Desert.
Manitoulin Island in Lake Huron, Canada holds the title of largest naturally occurring lake island by area. René-Levasseur Island in Manicouagan Reservoir, Quebec, Canada is the world's second-largest lake island of any kind.