I know my earning/ loss in 1099-B but turbo tax doesn't allow me to enter it manually, so is upgrade to premier mandatory in this case?
In order to enter investment sales from a 1099-B you have to either upgrade to TurboTax Premier Online or use any edition of the CD/Download TurboTax software. You cannot enter your 1099-B in Free Edition.
You might qualify to use IRS Free File Program delivered by TurboTax. It's at the following link, and the qualifications are listed there.
IRS Free File Program delivered by TurboTax
In order to enter investment sales from a 1099-B you have to either upgrade to TurboTax Premier Online or use any edition of the CD/Download TurboTax software. You cannot enter your 1099-B in Free Edition.
You might qualify to use IRS Free File Program delivered by TurboTax. It's at the following link, and the qualifications are listed there.
IRS Free File Program delivered by TurboTax
You must visit the IRS at https://www.irs.gov/filing/free-file-do-your-federal-taxes-for-free
to find truly free filing. Note that some include free state as well; that's important.
Also, there are other tax prep outfits that will do your Federal return for no charge, regardless of complexity or income.