that’s what a lot of people use, including me. I can tell you firsthand that 100% Poly Kitty String is really good to start with, if you’re not sure what your style is yet, or what type you’re into. I started with Yocala and wasn’t impressed, but I got a pack of Kitty at Cal States and I love it! Highly recommend trying it!
im wayyyyy past intermediate and i still haven’t learned Kamikaze XD i skipped over a lot of the tricks that didn’t appeal to me visually when i started out.
As far as strings i like kitty a lot, the neon yellow ones, i think they are the slims? Idk they were a gift. They are kinda grippy on your fingers and whip and slack really nice! Toxic dragon strings are really good too! Very expensive tho so idk why i just recommended them hahahaha.
And as far as your knots, forget about using your fingernails to untie them, get a paperclip a toothpick or any other small pointy object and pick them suckers apart, it works really good for axle knots (when the yoyo has the knot in between the two halves and causes the yoyo to not fully unroll) so you dont have to give the threads in your yoyo more wear down by unscrewing it just to get the axel knot out. Hope i helped buddy! Happy throwing!