Now that I am awake let me give a more detailed response.
What are abilities? They are no so much knowledge but your skill in a certain action. It can include information but what you know is certainly different from what you can do. Take Sorcery for Example. Normally, you would need to purchase Path Dots like a Mortal. But you are not Mortal. You are Exalted, and an Infernal at that. So you can more than get away with Sagacity being the load bearer here.
The same applies to driving a bus or a plane. A high rating in Ride may allow you to roll well but unless you know HOW to ride a plane, you would not be able to roll at all. OFC, as an Exalted, you can roll with a Penalty in some cases, but impossible rolls are still impossible.
So when MAKING a Demon, they may have the raw ability to do so by Drawing upon Primordial Essence and your Past lives but that does not mean they have knowledge, just the ability.
Now what is Past life? It is your Previous incarnations, a conglomeration of their memories, that has condensed into a singularity of gibberish and confusing mish mash of thoughts. One moment, you may be walking down the halls of the heavens, the next minute, you are fighthing in the Primordial War, then you are being killed by your Loyal Dragonblooded troops at Mount Meru.
There is no organization. You literally roll to pull useful information from it. It is not a neatly organized Library where you can go to the index and know the bookshelf where the book you want is. Nor is it like google. Each page of the book is stored somewhere in the library. Not the bookshelves but the library, even the restrooms. Heck, sometimes entire pages have been torn into tiny pieces and hidden.
So now lets look at what Sorcery is. It is divided into Workings and Paths. Here is what the charm says.
By the power of the Primordials, Creation came into existence and elements, deities and even life upon it. Sorcery is this power, filtered down through fractured glimpses of understanding that cannot begin to describe the intricate elegance of the universe. To be a sorcerer is to be mad with jagged shards of cosmic awareness and with will and might enough to impose that madness on the world.
Highlighted portions are the relevant part. Essentially, you have glimpsed the whole picture but you only have a few of the pieces and have to recreate it from something you say in a half remembered dream. Thus, you can only recreate a part of the picture and need to assemble the other pieces to complete the whole.
Primordial Initiation + Past lives + Defiler gives you a MASSIVE heads up. You do not need to purchase Rituals for example. You get them for free, once you have been initiated into a Sorcery. But that does not allow you to skip everything. You still need to put the Work in.
Workings are where the meat of Sorcery lie. They are Permanent effects upon reality. Where you can do anything from move rocks to rewrite the laws of Reality. This is what the Primordials used to make creation, the gods and many other things. They did not cast "Create Creation" but performed a Sorcerous Ritual to do it.
Now why do you need a Tutor? The answer is that the Primordials had essentially infinite resources and time. When making creation, it was in an era where time did not exist and they had infinite resource of the Wyld, both of which you do not have access to. So if you want to try and touch upon stuff that took Multiple Primordials an infinite amount of tries and resources to do? Expect to put the work in. This also applies to the Solars during their Rule.
Now, there are rules, limits etc. But it is possible, maybe not practical, but possible to recreate things from first principles, but you are once again taking about things that took multiple people multiple generations to do.
Hope this helps.