Thanks a lot, lot of extremely useful points.

I was able to make what I wanted. I share my basic box model here, all dimensions are from the spreadsheet. I’ll add more complexities for my personal project. https://drive.google.com/file/d/1VGQb9p0G_uOlvEQuEZNkt2TiBsSuiA73/view?usp=sharing

Aslo, Is there an easy way to retrieves all the sketches with dimensions in order to print it ?

Thanks, I created a first sketch+pad for the top plate on the XY plane, the the side plate on the XZ plane, now the side plate sit at the center of the top plate, how should I move it to the side of the top plate?

Thanks. I just discovered the spreadsheet and aliases, pretty straightforward to use the values in the sketch. Now I have yet to find out how to create multiple parts.

3D printing, I plan on placing the left angled side (of the top left sketch) on the printing bed, this way I should avoid supports.