This is a great place to look for starters, to address any specific needs your family might have: Mother Nature. The author, Dr. James Duke, has worked all over the world as a botanist, studying plants as medicine in different cultures. He has several books, such as this one available on Amazon.com;
Green Pharmacy Handbook. That's green as in plant, not "green living", for those FReepers who might have a coronary over the title!
If you do buy vitamins, make sure they are made from food grade materials, not vitamins such as Centrum or One a Day.
what do I need to know about Mg fire starters?
Again, from Amazon, "By scraping the "shaving edges" with the blade, you will accumulate a pile of magnesium shavings. Then simply scrape the "sparking insert" to ignite the shavings." mg fire starter
And ALWAYS have honey on hand. It never goes bad, is a great food source, and can be used medicinally inside and out. You can even wash your face and hair with it.
RE: herbal medicine...
Never too late to start on this, especially if you have kids. I started studying the topic in earnest about 15 years ago and I still feel I’ve just barely scratched the surface.
If I might suggest, start by getting a good herbal remedy book and just browsing. If any in your family have a particular illness or recurring symptom then look into the cultivation, preparation or storage of those herbs to begin with. Many times you’ll see an herb that is used repeatedly for many things, that might be something you want to learn about.
Not all the things I gather to use are things I can grow around here. Look at the plants that may be in the environment of the area where you live. Ask questions of folks that tend to have knowledge about this. Yes, many times those folks are the stereotypical liberal old-hippie types but if they have knowledge on the subject just make your mind a strainer and strain out the BS and keep the real knowledge.
One way to start is just to grow a few easy mints, sages and typical “cooking” herbs and start making some teas for yourself. See what the effects are of reputed calming or stimulating herbs.
Some I might suggest to start with for very everyday purposes to just keep around are horehound, catnip, lavender, spearmint, peppermint, sage, aloe of course, and the big anti-viral thing lemon balm.
Okay, probably ya’ll already know a lot of that stuff. But, just reconsidering things how I would start over again learning this topic.