I notice you're asking how to download CivilCAD for AutoCAD 2019 for free. CivilCAD is proprietary software developed by Arquinétesis, and downloading it without a valid license would violate copyright laws and software distribution agreements.
If you are looking for free tools for Civil Engineering within AutoCAD 2019, you should avoid pirated CivilCAD and look at these alternatives: descargar civilcad para autocad 2019 gratis
If you somehow find a working version, be aware of the compatibility nuances with AutoCAD 2019: I notice you're asking how to download CivilCAD
, permitiéndote probar sus capacidades en proyectos reales. Licencias Educativas: descargar civilcad para autocad 2019 gratis