AoA and ILS are very different things.
AoA is a measure of the angle between the wings and the relative wind. It is important for ensuring the right aircraft attitude on touch down and also for high performance maneuvers. The term “alpha” is also used for AoA. If you look at some HUDs you’ll see AoA displayed next to an alpha symbol. You might hear the term “high alpha maneuvers” used when reading about fighter jet and aerobatic aircraft performance capabilities. The F-18 for example can perform some high alpha / high AoA maneuvers since it has some unique design features with its flaps and wing.
ILS is a system used for precision landing consisting of a localizer and glide slope bar. The goal is to ensure proper glideslope and horizontal alignment when approaching a runway for touchdown.
To work, ILS requires on board ILS equipment and ground ILS equipment at a given airport in order to work.
In IF, GPS approaches are available for airfields not containing ILS. This is an advanced ILS type system using GPS to generate glideslope and localizer information vs radio signals from ground based ILS equipment.