Anyone train in martial arts?

I stop training many, many years ago, nearing 70. I but enjoy watching the martial arts world.
I have over 100 + books related to the martial arts world, I just enjoy reading them, plus almost the same amount on videos.

My goal was searching for a few techniques that anyone at any age can do without years of training. I have a few ideas?

Universal Kempo Karate, & Shotokan (short-time in Tang Soo do, Judo, Goju-ryu)

My flavorite book to read is “Musashi ” 900 pages, read it three times in three month. Musashi also wrote the “Book of Five Ring”. Read not only by martial artist, but by many business owners, leaders.

One technique very rarely taught? I found in just one book, “Biting”. If a bite is not treated, one in twenty people may die.