Get your taxes done using TurboTax

This confirms what I know but I don’t know how to enter it in TurboTax. The online expert told me I had to generate a 1099 of my own just showing a one time sell.  What i want to generate is an 8949 that will then become the information for the Box F. I could not get information on how to do that on TurboTax. Please give me some direction.