onUse

    @SubscribeEvent
    public void onUse(PlayerInteractEvent.RightClickItem event) {
        PlayerEntity player = event.getPlayer();
        Item item = event.getItemStack().getItem();
        CompoundNBT nbt = item.getDefaultInstance().getOrCreateTag();

        if (item == Items.WRITTEN_BOOK) {

            IHealthCapability health = player.getCapability(HealthCapability.HEALTH_CAPABILITY).orElse(null);
            ListNBT pages = new ListNBT();

            if (health.getMaxHealth() >= 2.0F && health.getMaxHealth() <= 6.0F) {
                pages.add(HealthBookUtils.setPageOne(player));
            } else if (health.getMaxHealth() >= 8.0F && health.getMaxHealth() <= 12.0F) {
                pages.add(2, HealthBookUtils.setPageTwo(player));
            }
        }
    }