Capital loss carryovers are entered on the Federal Carryover Worksheet.

Click the green "Where do I enter?" button and type "fed" to get there.  About 1/2 down starting on line 12.

However, just to back up a second, you may want to double-check the loss from the sale of real estate properly created a capital loss.  A loss from personal-use property is not deductible, and if it was from a rental or business, that loss would have been fully allowed in the year of the sale.  So only property that was not personal-use or business/rental use would have created a capital loss carryover.