Capital gains loss carryover from sale of stocks is not showing up as a deduction for my 2019 taxes. how do I get the carryover to show up on my list of deductions?

If you used TurboTax last year and ended up with a loss carry over, and transferred last year's income tax return into this year's income tax return, then the carried over loss has been applied though you won't see it when you complete the "Stocks, Mutual Funds, Bonds, Other" interview.  You basically have to wait until you can see Schedule D - you look at that Schedule before you file - to see that it's there.

If you didn't use TurboTax last year then you enter the carried forward figure(s) using the "Capital Loss Carryover" interview.