Fusion 360 produces technical drawings from your 3d models - it's incredibly easy to produce orthographic projections. We'll finish this tutorial by producing an orthographic, dimensioned projection of your lego brick.
34. Select drawing from the Fusion mode menu, select "From Design" then accept the defaults for the drawing size etc and click ok.
35. Drop the end view in the middle on the left hand side.
Change the scale of the drawing to 3:1, switch style to "Visible edges".
Press P (for project) and drag out plan/base views above and below, above/below 3d projections off to the right, then hit enter once all views are placed.
36. In order for someone else to be able to build our Lego brick model they'd need to be able to see measurements of the brick, so now we dimension our orthographic projection.
Press D, then select the two points you want to dimension, drag out the measurement and left click.
Repeat until its dimensioned similarly to this (don't worry about the differing layout.