Imported 1099-B transactions, but now can't edit for ones inherited.

Using the desktop version on my MacBook Pro, I downloaded the stock sales and got to where it asks if I purchased the stocks or if they were inherited. I was going through that, but somehow clicked out of it, and now I can't get back to where I would address this. How are those transactions treated? Can I go directly to form 8949 and designate the ones that were inherited? What happens if I don't designate that? They have the cost basis entered as of the date of my mom's death. What other information would need to be noted?