when you die, you'll keep your items. you can save your progress at certain points depending on what path you take. if you take the normal 'follow the light' path, you will have a bright shrine you can save at. if you try to take out every god, the bright shrines will soon stop showing up, and become chaos spires. the chaos spires will be more separated than the bright shrines will be. however, if you try try to find the truth, there will be rarely any save points. there will only be an early light shrine that will soon turn into a chaos spire, and then a sculpture of the seeker's will in the middle of the game, then there will be a save before the final boss of the truth seeker path.