Freecad is an open source CAD program to create your own designs or drawing in 2D or 3D environment. You can download it, if you want to try. I have different video tutorials to learn how to use freecad.
This technical drawing can be used in CAD programs to practice.
Part Design video tutorial includes
- Creating constraints and dimensions in FreeCAD
- How to use constrain lock
- Mirroring parts in part design
- Creating additive pipe in FreeCAD
- How to change position of sketch in FreeCAD