All the examples in this folder uses eframe to set up a window for egui. Some examples are specific to eframe, but many are applicable to any egui integration.
There are a lot more examples at https://www.egui.rs, and it has links to the source code of each example.
Also check out the official docs at https://docs.rs/egui and https://docs.rs/eframe.
Note that all the examples on master are for the latest master version of egui.
If you want to look for examples for a specific version of egui, go to that tag, e.g. https://github.com/emilk/egui/tree/latest/examples.