Recreate a CMS from PHP

I’ve built a kind of cms in php, and I wonder if someone could give me
some hints on how to do this in RoR. Doesn’t have to be much, just so I
can get an idea of what I should learn and tackle as a new user of both
Ruby and RoR.

The system is built with a core of users and on that different modules.
Users are given access depending on what user group they belong to, and
from the other end an administrator can assign the different parts of a
module a group name. Normal and straight forward. I also have a language
file connecting variables with the particular word of the selected
language in each module with variables in the files. A greeting on the
first page is then given in the language the user has assigned. So the
system is based on modules that can act separate from each-other.

The main interface is a page where you have a top and a menu on the left
and content in the center. It’s the same in each module. The first
concern is the menu that checks what module it’s in and what to show
depending on the user group and language ( You can always reach the
different modules in the same menu). How can I use RoR to make that menu
as an object that I can include in every page but still be always the
same? Do I make a class of my own or method or what?

I bought the book “Agile Web D. with Rails” and try to learn in
the same time. But a few hints would be great. For example; my current
db has table names like “adm_users” (mysql). Can I still use that, or
what about this thing with model name and table names in plural?

Sorry for a long and complex question, but I’m eager to get started and
want to get into the right direction as soon as possible. I started to
learn Ruby and it seems easy and rather fast to learn. Ror is more
complex to me.

First Review Your database schema
Second create your migrations and models for this schema
Third provide any desired login so you can interact normally with the
application
Fourth think what do I want to get or be able to do on this page and
then implement your controller/view

HTTP is stateless so what page your on should not affect what page your
going to except by what ever you have in the…
-URL
-SESSION
-COOKIES

use inbuilt tests so you can seed these and avoid breaking anything down
the road.

Now go build and think what can I do better next time