The data pack gives you two different crafting recipes for the Supplementaries quiver. Both use normal survival materials, so you no longer have to find a quiver in the world or spawn one with commands.
Looking up the recipes
1. Place or open a crafting table.
2. Click the green recipe book icon and type quiver into the search bar.
3. If the quiver appears, click it to see the ingredients and their layout.
4. If you use a recipe-viewer mod, search for the quiver there and view its recipes. Both versions should show up.
The vanilla recipe book usually unlocks a recipe after you have picked up one of its ingredients. If nothing appears yet, gather some basic materials and check again.
Choosing a recipe and crafting
1. Compare the two recipes and pick the one whose materials you already have or can get faster.
2. Collect the ingredients shown in the recipe.
3. Place them in the crafting grid in the arrangement displayed. You can also click the recipe in the recipe book to fill the grid automatically.
4. Take the quiver from the output slot.
Having two options means you can usually craft a quiver from whatever your base or biome provides.