- Change only the following in-between the ""(this is where text goes) Quest(name of the book if you don't want it to be called Quest) Steam(author of the book) Craft a Lodestone!(the quest you want the player to do): ({"text": "\n"} this is a line break in the book)

{
          "type": "minecraft:item",
          "name": "minecraft:written_book",
          "weight": 1,
          "quality": 1,
          "functions": [
            {
              "function": "minecraft:set_book_cover",
              "title": "Quest",
              "author": "Steam"
            },
            {
              "function": "minecraft:set_written_book_pages",
              "pages": [
                {
                  "raw": 
                  [
                    {"text":"Craft a Lodestone!"},
                    {"text": "\n"},
                    {"text":"You will need:"},
                    {"text": "\n"},
                    {"text":"- 8 Chiseled Stone Bricks"},
                    {"text": "\n"},
                    {"text":"- 1 Iron Ingot"}
                  ]
                }
              ],
              "mode": "append"
            }
          ]
        },

- Once you have made the changes you want you can copy paste this into the quests.json that is the loot table for quests
you want to paste it after this section here:

{
  "pools": [
    {
      "rolls": 1,
      "entries": [
(paste your quest here)