You can't use Online TurboTax for a 2016 return at this point in time; it shutdown for 2016 in late October. Now it is open again, but only for 2017 returns.
You could prepare the 2016 returns in desktop software (CD/download) installed on your computer if it meets the minimum system requirements.
I see you are using Windows Vista. 2016 TurboTax desktop version requires Vista SP2 or higher. Do you have Service Pack 2 or higher?
If you meet the requirements, you can purchase the software from TurboTax at this link below, or you might be able to find it at a discount at a reputable authorized retailer such as Amazon.
Or did you already start a 2016 online return prior to the shutdown? If so, and if you want to download to continue it, the FAQ below tells you how. If you already paid for the 2016 online return, TurboTax Support should furnish you the software.
I see you recently looked at some articles about amending an online return. So please explain exactly what it is you need to do. Your original question above doesn't say anything about having started a 2016 return or needing to amend a return.