Game concept
Provisions
The game also links it as Provision.
From the game's encyclopedia
Provisions represent the total amount of food, water, and shelter a Camp can provide.
Camps lose Provisions while moving Location. Exactly how much is affected by size of their Men-at-Arms, the Terrain moved across, and what Officers are currently hired.
Camp followers running low on Provisions will start suffering Privation events: starting with Characters quickly losing Opinion of their leader, escalating rapidly to starvation and death.
Provisions can be refilled when stationary by requesting them from Patrons, taking a Decision, or as Contract rewards.
The game's text for patch 1.20.1.2. Words in blue are entries of the encyclopedia: hover one to read it, as in the game.
Provisions is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Provisions represent the total amount of food, water, and shelter a Camp can provide." It covers Privation. The game also links it as Provision. Patch 1.20.1.2, from game/common/game_concepts/00_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/00_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.