Alpine Touring ski boots are designed for use in the back country and off piste skiing. They utilize strong and lightweight plastic as well as a walk mode to make skinning and boot packing much easier and less energy consuming. They come in a variety of widths to suit both narrow and wide feet, and are generally used by advanced skiers.
Most people choose to make their ski boot more comfortable by adding custom footbeds and using a proper technical ski sock. It's definitely worthwhile booking an appointment with an experience ski bootfitter who can ask the right questions, correctly analyse your biomechanics and recommend whether a alpine touring ski boot will be a good fit you.