TurboTax is not offering any type of Advance Loan on a 2019 tax refund at this time.  It is not known if TurboTax will offer an Advance for the 2019 tax year, but if they do it will not be until either late January or early February.  If TurboTax follows the same procedure as in tax year 2018 you will not be able to request an Advance.  It will only be offered to select users of the software before they file their tax returns which include a tax refund.

Because TurboTax does not, and has never, offered loans.  Last year they did offer refund "advances" (not loans) to some selected customers, but ONLY after the customer has filed their Federal tax return using TurboTax and it was accepted by the IRS.   The customer also had to agree to have their refund direct deposited and sent to TurboTax so that the advance could be recovered.  It is not known at this time if that will be offered again for 2019 tax returns.  If it is, it will not be until January or February 2020 when the IRS starts processing tax returns.

A bit of history ...  

When they first started doing  these RAL (refund anticipation loans) the banks got a debt indicator from the IRS so they knew if the loan was going to be good.  But several years ago the debt indicator was removed so the banks started doing refund loans which were not really advances on your refund but in reality is just a signature loan using the anticipated refund as a type of collateral.   Very few banks (via a tax prep software) still do any of these risky loans any longer ... good luck finding one that doesn't charge you an arm and 2 legs.