If you have a single member LLC, you do not need a separate tax return for your business, you can file as a Schedule C on your 1040. You can, however, elect for your LLC to be taxed as an S-Corp and then you will file a Form 1120S separately for your business. To do this you must file Form 2553. If your LLC has partners, you have to file a separate tax return Form 1065 for partnership. If you have partners, I can explain further.
