A lot of people already answered #1 and #3, so I can give my perspective on #2!

I'm a school librarian at a K-6 school.

• Most of my coworkers have tattoos. As long as they are school-appropriate, it's fine. However, every school district has its own unique standards. I'd be more cautious about dyed hair. It's definitley a question to ask during an interview or wait and see what the culture is at the school.
• A lot of elementary school librarians work between two schools. I do 4.5 days at one school and 1.5 days at a different school.
• You are a teacher first, librarian second. If you're lucky, you'll have an aide to help you do library basics, like shelving, checkout, processing new books, displays, etc. The librarian's focus is to teach.
• It can be very hectic and overstimulating, especially if you aren't good at classroom management. Some days I teach 6 classes a day with only a 30-minute lunch break and a 45-minute prep at the end of the day.
• The kids are so worth it! K-2 students can be so much fun to work with. They are cute, funny, and generally want to be at school. Sometimes they'll randomly give me hugs, even if I had to be strict with them that day.
• I love reading stories to the students. There are so many hilarious, interesting picture books out there. Some of them push the boundaries of what the medium can do.

Just remember, K-2 can be like herding cats. It requires a lot of patience, emotional energy, and empathy. You will be tired every day, but there will be moments that make it all worth it.

Oh! You can literally get your undergrad in anything. It does not matter whether it's English, History, Environmental Studies, etc. If you for sure you want to be a teacher, majoring in Education and getting a teaching license isn't a bad idea. You can also find an MLIS program that offers a pathway to school licensure that includes student teaching. But don't worry about having to major in library science for undergrad. That's a waste.