What I consider to be "the basics" differ for each person and even differ among subjects each individual practices and/or studies. For example, there were things I inherently knew or learned at a young age that I didn't put words to or even thought of them as being magical until I was later aware of occultism and its communities - while there are other things that I am in the process of learning and I've found there are different things I take well to and other things I might need to give more attention to overcome obstacles (most of which I set for myself subconsciously).
What I consider to be the basics are what we how we understand a subject works in study as well as practice. For this, I don't adhere to any singular set of basics as I piece-meal and develop my understanding as I go along.
Altered states, visions, & dream lucidity - some of the subjects I inherently knew as well as learned when I was young simply by paying attention as well as getting into the flow of my brain. A lot of this was simply self exploration as well as bits and pieces of advice.
Sigils, wards, and basic curses - these are things I took well to in the beginning of my earnest study and have been main aspects of my personal craft (as I do identify as a Witch, among other things) that I have developed over the years.
Working with spirits and the etheric energy of the land - these were not quite as early on as the others, though I was still in a budding stage when I began them and they have shaped many of my experiences.
Working with deities and other human beings - these particular subjects were ones I felt I was simply blocked off from for years until they happened largely without my provocation. I felt disconnected until my first experiences, which were profound and not nearly as frequent. However, once I learned what an experience was like, I was able to experience the rest more fluidly and each experience is different from the last. For that, it adds to a repertoire of what possible experiences can be had that I can relate to others with.
Even outside of specific practices (of which some are shown as examples), certain studies shaped my worldview that continues to grow and develop. I began my occult journey consciously with three books that heavily influenced how I understand and interact with reality even today, though I have formed my own understanding and opinions in addition to them. Those books were Essential Wicca by Paul Tuitean and Estelle Daniels, Druid Magic by Maya Magee Sutton and Nicholas Mann, and The Weiser Concise Guide to Alchemy by Brian Cotnoir and edited by James Wasserman. Of the three, I only continue Alchemic studies, though each book played an important part in my understanding not only for the material discusses, but some of the mentalities approached in them.
Essential Wicca - I started out identifying as Wiccan, though I never truly felt connected to the Lord and Lady, nor was I initiated into a coven. By the current standards I hold myself to, I cannot say I was actually Wiccan as well as the fact that this book is not traditional; it is NeoWicca.
What this book taught me, however, that I still hold onto is that every worldview has as much legitimacy as any I ascribe to - later going onto developing the understanding that we cannot prove or disprove anything beyond physical reality as we cannot isolate variables enough to measure what I understand to be subtle (nonphysical) energy. It is important to note that not everyone who is spiritual or religious believes in subtle energy, even though it is intrinsic to my path.
With it, I had exposure to various paths, traditions, practices, studies, tools, and mentalities. What's important about this is that I could get a feel for what was out there and then dive into what interested me more. Eventually there were topics that I learned a lot about (and still am) while other subjects covered aren't really my thing. What I liked about the book is that half of it wasn't even about Wicca, but about how to go about learning things and being safe about them.
Druid Magic - what is important to note here is that I was never Celtic, nor was this book about traditional Celtic Pagan practices. Rather, it was a modern interpretation of practices based on various myths in the lore as well as other modern practices that influenced the writers. It offered a more Shamanistic outlook in terms of spirit work and trance as well as the mentalities that can come along with them and even had exercises at the end of each chapter that were enjoyable to partake in that were often more fluid and dynamic than the ritualistic aspects of Wicca I previously had been exposed to.
Currently I don't do anything with Celtic Paganism, though I still hold to and have developed some of the mentalities and techniques offered in the book.
The Weiser Concise Guide to Alchemy - my bread and butter for beginning to understand how reality works in my own perspective. Alchemy itself is a very broad subject that no two people or even works among the same person were alike. Rather, people take the understanding that can be from religion, philosophy, science, art, medicine, and the like with the core goals in mind of the process of betterment and the catalystic process that gets us there. To me, that's what Alchemy is, no matter what form it takes. It shapes not only my worldview in terms of spirituality, but my mundane life in terms of how I process information and tackle each situation as it arises.
I consider myself an Alchemist as I adhere to the two core values I presented above, though it is an intensely personal journey that really only applies to me. For this, I do not often write on the subject as it is an umbrella term that is ultimately piece-mealed in every work.
Now, the point of talking about these books isn't that I believe they should be read by everyone as they only apply to my path and how I understand reality, studies, and practices; it is showing that exposure to different subjects, taken with a grain of salt as well as being digested personally, is how one can build their understanding of what is their set of "basics."
No one truly ever stops using what they understood before, even if that experience is no longer continued. The point is that every aspect of life influences our understanding, opinions, and decisions. Beyond what I'd already been practicing before I started in earnest, I spent a year of study where other practices were largely dorment. It will be different for you as it is different for everyone.
This is bit of advice I feel might have helped me more - trial and error can help you understand your flow of learning by incorporating study, understanding, practice, and the practicality of applying what you understand. You may find you take more to study or you might find you're more hands on. It is different for everyone, but if you expose yourself to different forms of learning, you can instinctly explore styles, subjects, and mentalities that are more natural for you.
Remember to not get discouraged if you feel you are taking longer or simply not getting something. You have your whole life ahead of you to get into your niche.