If your single member LLC has not incorporated in your state, then your business, for tax purposes, is a disregarded entity. You report your income and expenses on a Schedule C. The Schedule C is part of and included with your personal tax return, Form 1040.
A net profit or net loss from the your business is reported on Schedule C. The gain or loss flows to Schedule 1 Line 3 which flows to your Form 1040 Line 7a.
Self-employment taxes on your net profit is reported on Schedule SE. This amount flows to Schedule 2 Line 4 which flows to your Form 1040 Line 15.
