Thank you for the welcome! I apologize for dropping that comment and then dropping off the face of the earth
I appreciate your point, criticism or not! Teaching is clearly not my strong suit and I don't have kids (yet) 
so please allow me to have another go on that front!@Ischgl99 nailed the reasoning for using the project feature.
Just a bit of 50,000-foot view may help. My original "CAD" of choice was SketchUp for 10+ years. In that program, if you're familiar, everything is constrained with either a dimension or an angle. The problem arises if one of those dimensions changes, everything is out of whack.
Fusion 360 on the other hand is a "Parametric" modeler, which means that if the model is set up correctly, one dimension can be changed and the entire model will update to reflect that change without breaking anything. While you can use the "sketch and dimension" workflow of SketchUp, it really leaves a lot of the functionality of F360 on the table. The real power of Fusion is constraints. For example, the reason I used two construction lines (shortcut "x" by the way) of equal length instead of using a dimension to center the sketch is that the sketch will be centered whether it's 1in wide or 2.875in wide.
The habit from SketchUp that I have struggled with is adding dimensions too soon. Ideally, you add as many constraints as you possibly can before adding a dimension. This way the sketch is scalable and the only dimensions that you need to add are those that are critical to the use of the part.
Sorry if I made things more confusing
