How do you go about modelling the inside of something… Like a room or a corridor?
I mean, how do you start?
Do you start with single plane or flatten cube and model one wall at a time, or do you start by creating a cube/form and the plunge inside (if that is possible) and model it from there?
I’m pretty noob in this field, so forgive me if this is a dumb question.
If you are only going to see it from the inside you can just use intersecting planes. If you need details like windows and doorways, just use loop cut tool and make holes where they need to be, then model the window or door ( plus frame ) and position it in the hole. arrange your walls and objects on different layers so that you can toggle them on and off and they won’t obstruct your view while modeling.
By jumping inside you’ll sooner or later will find that “shell” can be a distraction, so you hide it all or some part. You need it just to get the rough idea of the proportions of things or later, for the final adjustments. Jumping “out” of the shell - switching to the Local view can be another way of modeling parts. It can be separate blend file where you model just one thing, then Append or Link it to the “inside” which is another file.
More than often you want just a part of that “something” inside of which you are dealing with. It all depends on what you do and the complexity of it.
Check out the tools and look for what looks easier for you.
Thanks!
I went with planes finally. This way I think I’ll be able to model different walls, floor and ceiling sections which I’ll assemble, a bit like tiles, to create what I want.
Now I have to move to the next few step on this Blender journey :
1- Plan and make sketch of what I want to do.
2- Learn how to scale (unit of measure) work in Blender so my model fit my design.
3- Learn how to model 
4- Move on to texturing and lighting…
5- …
6- Profit!