SketchUp 布局是免费的吗？

No, but SketchUp Make is free and can provide mostly what Layout offers.
Although you can try Layout for free with a SketchUp Pro trial.
Just search the net for SketchUp pro and include in the search for the software provider Brimble.
Unless you are a professional user, Layout does not necessarily make things easier because it is a separate companion program to Sketchup.
If you are going to spend a great deal of time learning, why not just spend time learning more about SketchUp Make 2017 (that is free) that will more than likely achieve what you require.
Layout is really just publishing software. SketchUp itself along with default software on your PC, or in your ink printer software is more than likely satisfactory enough for publishing.
You may require Layout If you require your 3D models to convert into 2D technical drawings. Again SketchUp Make 2017 can do a pretty good job, even for some professionals.
如何！
Open up SketchUp Make 2017
去，
Everything you see outlined in red is all you need to achieve everything you see in the animation below it.



Everything is made by the view options above.
3D by ticking the perspective box on the left and the iso (3D) box on the right.
2D by ticking parallel projection on the left, and the 2d view you require on the right
Save all your views as scenes, like you can see in the animation, (highlighted in blue) each scene or view with the click of your mouse.
SketchUp automatically makes the transitions between scenes for you.
SketchUp will even make an mp4 video for you automatically, that looks similar to the gif animation below. (File, export, animation, video). You can check to see what it looks like before you do. (View, animation, play).



Try it out as it is great fun if you are into scale technical drawings, or desire to make presentations similar or completely different to the above. Or screenshots cleaned up and manipulated with Microsoft Paint, and scaled by your ink printers software.
To acquire SketchUp Make 2017, (the free version) search for SketchUp Make 2017 Brimble the software developer.