SolidWorks is one of the most widely used CAD programs in machine design. The good news: you don't need to know every menu to model your first part. Four steps are enough.
1. Sketch on the right plane
Pick the part's most characteristic view and start the sketch on that plane. Draw the lines roughly; you'll set the dimensions next.
2. A fully defined sketch
Use smart dimensions and relations until the sketch is fully defined. When the lines turn black, it's ready. This keeps the model intact when you change a dimension later.
3. Extrude and cut
Turn the sketch into a solid, then add holes and pockets with cut features. The Hole Wizard gives you standard sizes automatically.
4. The drawing
Create a drawing from the model: three views, dimensions and tolerances. This is the document that goes to whoever makes the part.
In the lab's computer workshop you can model in SolidWorks and print the same day on a 3D printer.