I have submitted my state and federal taxes but I am the sole proprietor of a business.. Can I file another tax return on Turbo tax Home and Business for this business?

Since you are a sole proprietor, your business taxes get filed with your personal taxes (on a Schedule C).  It is part of your Form 1040.  You can't file a second personal return, but you can (and should) file an amended federal tax return and add your self-employment income and expenses.  And yes, you can use Home and Business to do this.  See the link below for instructions.   See the image below to see what section you use to add the Schedule C.  You can get to this section by typing    sch c   in the search/Find box at the top and using the Jump to link.  

How do I amend my 2018 return in the TurboTax CD Download version?