If there are two or more players in the world, you have a loot table like the one below, and then they give players via /loot give @a loot <name>, all players get the same number and type of items.

{  "pools": [ { "rolls": 1, "entries":  [

{ "type": "item", "name": "minecraft:white_wool" }

, { "type": "item", "name": "minecraft:black_wool" } ] } ]}