The answer to what you need is: It Depends. It depends on what sort of volume, accuracy and variety you are seeking. the basics of reloading consist of: taking a fired case, removing spent primer, sizing case down so that it will fit easily into the guns chamber and provide firmness to hold the bullet, trimming off excess case length. Seating the new primer, measuring and pouring in the powder charge and seating the bullet.
All of this can be accomplished with a simple set of hand tools, a scale and a case trimmer. If you intend to load a box of cartridges per year, these will be sufficient. As the number of cases and the desired accuracy and number of different cartridges increases, so does the equipment needed.