941 & 940 - ENGAGE CPAs

Forms 941 and 940 are only required for businesses that pay employees payroll. This is an important distinction. Only if you're paying either yourself or employees' payroll, with taxes withheld, do you need to file 941s quarterly and then the 940 at the end of the year.
As the owner of the business, you can only set up payroll for yourself if your business is set up as an S-Corporation or C-Corporation. All other entity types do not allow you to pay yourself a payroll. However, any entity type can pay employees payroll, even sole proprietors.
Form 941 is filed quarterly with the IRS, it's the payroll tax form that tells the IRS how much in wages you've paid to yourself or employees in the prior quarter, how much in federal taxes employees had withheld from their pay and how much in social security and medicare tax you've paid in. You'll file 941s for all four quarters of the year, and then at year-end, you'll also file the 940 which totals up all of the information from the four quarterly filings.
The good news is that payroll companies are everywhere and they're really good at handling all payroll tax-related filings. As long as they know your account numbers, EINs, and all the information about your employees, they'll know exactly how much to withhold from each employee and will be able to file these payroll tax returns with the IRS on your behalf, automatically every quarter and year.