There's a gazillion tutorials out there and I'll just choose one for the total beginner. Could you recommend a specific one?
The ones I used are hopelessly outdated by now. Here's what I know of/can recommend:
MangoJelly Solutions for FreeCAD, search his channel for beginner videos. His latest FreeCAD beginner video. https://www.youtube.com/watch?v=9cqs3oTzpac
Too Tall Toby, search the channel for 'beginner' or 'tutorial' Deals with SolidWorks, Fusion, Inventor, Onshape and some FreeCAD https://www.youtube.com/@TooTallToby
Edit: OffsetCAD and 'Adventures in Creation' are two other FreeCAD channels I sometimes watch. https://www.youtube.com/@OffsetCAD https://www.youtube.com/@Adventuresincreation
What software are you using? Edit: Saw your other comment. FreeCAD it is.