There is nothing complicated here. Simply follow the next steps:
1.Open your image in Luminar Neo and select the SkyAI tool.
2.SkyAI automatically detects the sky in your photo.
3.Choose a suitable blue sky preset from the provided options.
4.To use a custom sky, click on the option to add your own sky image.
5.Adjust blending, horizon, and other settings seamlessly to integrate the new sky.
6.Apply the changes and save your edited image.