You can just enter the carryover. However, you can't just skip years. If you did not take it in 2019, you will have to amend and include it. At that point, if there is anything left, you can use it in 2020.
To enter,
just open your TurboTax return, search for capital loss carryover, and then click the "Jump to" link in the search results.
We'll take you to the screen where you can enter that info from your prior year return.
