If you have at least 2 member LLC, file tax return Form 1065 and

If you have at least 2 member LLC, file tax return Form 1065 and  extension Form 7004( due by 3/15/21, already past due ).

If you did not form a at least 2 member LLC or any other legal entity for federal income tax purpose, you will report your rental income under Schedule E of your individual return . Then file extension Form 4868 by 5/17/2021 this year for federal extension. You need to check your state due date to file state extension if needed.