I'm still learning!!
I discovered I needed a thimble to help plunge the needle (by pressing on the eye end) while doing hand sewing through heavier thicker fabric - and tried several thimbles on middle finger of my right hand. Didn't like any of them. So I still suffer.
Then I started needle turn applique. "Plunging" the needle was not a problem but "catching" and "directing" the needle from under the fabric required another thimble. For this I tried several of the thimbles I acquired from the previous experiment and the leather needle with a tight fit and an opening for a long fingernail is the one I like best.
So my learning was all by myself and by trial and error. Mom never taught me to use a thimble (although she taught me to sew, we didn't do much hand sewing that required a needle - mostly just hem's), and I never did any sewing that required one while taking sewing classes in school.