hiii i have lived in spain for a few years and it has changed who i am and how i see life so positively!! im v jealous you're just starting the whole experience
re: the job—i'm not teaching atm but did for the three years before. i didn't get a TEFOL certificate so i taught through the auxiliars program (i was a teaching assistant). in my case, it was super chill, i didn't have to plan lessons and the teachers helped me a lot. in any case, most public schools in spain run from 9-2 which is a work schedule i'll probably miss for the rest of my life. private schools generally run on a standard 9-5 schedule. the main problem you'll come across in the schools is poor organization and communication. my main piece of advice is brushing up on language skills if necessary—knowing spanish helps you communicate with the kids and the teachers a lot better. to be honest, the job had almost nothing to do with why i moved here, i just wanted to live in spain. that was mostly not a problem. my main issue with the job was being bored.
okay, work aside—life in spain is a dream. spaniards value work much less than we do in the us, and it's a more social, laid-back culture. take advantage of it!! travel around spain—it's pretty cheap and there is sooo much to see. i never experienced "culture shock" or anything like that, but i live in madrid so it's maybe easier than in a pueblo. that doesn't mean it's always easy or that it doesn't take a bit of time to adapt, but i don't personally know anyone who has moved here and had a negative experience. sooo anyways idk what else to add but rest assured you're making a great decision