30k uses a different organisation to 7ed, primarily, there are no set formations.
The most commonly used force organsiation is the Age of Darkness Force Org Table.
This is very similar to the old Combined Arms chart with some modifications.
1. Rites of war modify the Age of Darkness force organisation. A particular RoW will demand you take certain units, transports, or more compulsory troops etc.
In exchange, you get some benefits like 'terminators / predators / veterans are troops' etc.
You will also gain some special rules associated with that RoW.
The Legiones Astartes <your legion> special rule is analagous to Chapter Tactics. This gives the legion thier flavour and style.
2. There is a list of standard Rites of War in the Legiones Astartes book. These are the methods that every legion would have access to.
There are also legion-specific Rites that show how certain legions would do things differently.
3. First and foremost, every legion had access to everything.
Alpha Legion artillery companies and iron warriors jetbike companies are all things those legions would have possessed.
Beyond the grenade change and the invisibility change I don't think there is any reason to replace a 7ed rulebook for the AoD rulebook.
Just make sure these changes are kept consistent.
4. You need these: https://www.forgeworld.co.uk/en-GB/The-Legiones-Astartes-Army-List-Collection-2017
One has the generic legion units in, the other has the legion specific units, characters and rules in.
Land Raiders are an acceptable delivery method for most units. They can even be taken as dedicated transports in certain Rites of War.