If you have no income at all from the activity, the IRS considers it a hobby, not a business. If it produces no income at all, you do not have to report it.
If you have expenses for a hobby, you can claim an itemized deduction for the expenses, but only up to the amount of income from the hobby. If you have no income from it, you cannot deduct any expenses.
A single-member LLC is disregarded for federal income tax purposes. As far as your federal tax return is concerned, the LLC doesn't exist.
