Hello, does anyone know how to edit "Forecast Type" dropdown options on an opportunity? I cannot find this in lists and it does not show me an internal ID

I don't think you're supposed to be able to edit them. I've not used forecasting in NS, but the documentation suggests the fields are hard-coded, as they drive different forecasts. See https://system.netsuite.com/app/help/helpcenter.nl?fid=section_N1047903.html

Thank you