Your situation is not yet clear. You need to provide more information about what all you have already done and need to do.
First of all, what tax year? Is it a 1099 for 2018? If 2018, was the return prepared in Online TurboTax or desktop software (CD/download)? What edition did you use (Deluxe, Premier, etc.)?
What kind of 1099? Is it a 1099-B, 1099-INT, 1099-DIV, 1099-R, or something else?
You didn't say if you have already filed your return or not. If this is a 1099 for 2018, have you already filed your 2018 return, or is it still unfiled and you're asking how go to back to add the 1099 prior to filing? If you have already filed, was the efile accepted? If so, then I assume you are asking how to prepare an amended return to include the 1099. We can tell you more when you provide the additional info to clarify all that.
"original TurboTax maybe doesn't allow upload?"
What does that mean? By "upload", do you mean import the 1099? It is possible to import a 1099 into TurboTax if the financial institution is a participating import partner with TurboTax. And what do you mean by "original TurboTax"? Are you asking how to open an unfiled 2018 Online return back up to add the 1099?
I'm not sure why you are asking about "would I have to buy new software." You should be able to use your current product once it's clear what you need to do.
