Yes, if you file schedule C with your EIN and dba, it will be part of your personal 1040 return. And you pay self employment tax under your ssn.
Unless you have a Single Member LLC that elects to be an S corp. Then you file a separate LLC 1120 S Business return. What kind of separate Business return will you be filing?
I want to have a separate tax filing so the LLC S corp is where I need to make my business so to have them separate? Where is the best place to get my LLS S corp created? Can I di it online? I have my EIN number to create a bank account.
Where is the best place to get my LLS S corp created?
You should definitely consult a tax professional if you are seriously considering this change.
Having said that, you would need to file Form 2553 no more than 2 months and 15 days after the beginning of the tax year the election is to take effect or any time during the tax year preceding the tax year it is to take effect.