Even if you don't get out much, you probably know that modern civilization is increasingly specialized. Brace yourself, joke coming.
Nowadays people are so specialized, they know more and more about practically nothing.
That isn't me. I am a Jill of all trades, so that means I know less and less about almost everything.
A person who is well prepared for long term or TEOTAWKI (The End Of The World As We Know It), disasters, has to be a jack of all trades. You probably won't have a phone book to use even if you do have a phone to call a plumber or a vet. The chances that you will even be able to call a doctor, are also slim.
This means if you want that kind of work done, you will have to do it yourself. You will have to decide what your priorities are in order to make best use of your time. No matter how fast you read and learn, you will probably not be able to learn everything that you might find useful.
Medicine is one of the types of learning that I have given some priority to. I don't plan to do brain surgery, but I am learning as much preventive medicine as I can manage, along with uses of plants native to my area or plants that are
easy to get seeds for and grow.
I used Maslow's Hierarchy of Needs to help me make decisions about what subjects to learn first and spend more time on. This is reflected in my choices of posts for this blog. Even if your ideas of what kinds of knowledge are most important vary from mine, we most likely agree in general about the things that are in the top area of our hierarchy.
I have not covered much about clothing in my blog posts, although I do put it up there fairly high on my hierarchy of needs. I have put a fair amount of time for many years into learning enough to clothe myself and others from head to foot, for warmth and protection.
If you manage to learn to produce one type of clothing, headgear, or footwear that is acceptable, then you have a chance that you may be able to trade it for other items that you do not make. I think it is a good idea to take that approach and then add something else that you can make, one at a time.
The Paris fashion designers can breathe easy as far as I am concerned, but I can cut out basic patterns for most simple clothing. There have been periods of history where a single garment or outfit would have to last a lifetime for each person. Bear that in mind to take a lot of pressure off of yourself for clothing needs. The same idea might help with the rest of your hierarchy of needs. You only need to learn enough to get by.