it's nowhere in particular and Turbotax doesn't compute it.
you need to use form 1045 schedule A to compute it
https://www.irs.gov/pub/irs-pdf/f1045.pdf
the bad news is unless you included an election to carry forward the 2020 NOL, assuming you had one, you must now carry back that NOL to 2015 and then forward. sadly Turbotax no longer sells or supports the 2015 app which leaves Turbotax users (you can finish the sentence). be wary of offerings on the web or elsewhere for the apps prior to 2018. they are unsupported, can't be updated and no state apps are available.
