SketchUp Newbie help

I’m new to tutorial and can’t seem to figure out how to do some basic designing.
I’m busy converting a Sprinter Van and have taken some measurements of the inside of the van and now I want to draw up my design in Sketchup before starting the wood work.
I’ve taken measurements and have looked around for a video showing me how I build a design with real world measurements and none have help me so here I am asking the forum.

If I have a wheel covering that is 93cm from the back door how would I place the wheel covering which is 92cm x22 and 26cm height in Sketchup? Are there any real world videos showing how people use Sketchup in the real world making designs with actual real world measurements to be places in precise locations in SketchUp

There is no point in us retyping the user guide in the forum:

You should go through (completely) this chapter and all it’s pages:

I would think that is how most users intend to use SketchUp.

And to play with locations of created objects (say your wheel covering) in your design, be sure to work with grouped geometry. SketchUp’s edges in one and the same level are sticky. Groups and components won’t stick to other geometry.
Take some time to create a real basic design (some simple boxes inside a large box unlike your Van) and with the tutorials available your time invested will be worthwhile.
SketchUp Help may not be easy to navigate when searching. Here is an old pdf file of an ealier version of SketchUp that may help a lot in reading about how to input exact dimensions per tool (and a lot more).
It’s old but most of it is still “valide”