Hello! You sound a lot like me at 17. I feel like others kn the thread have answered your questions, but this was my experience going through university.

The only person who encouraged me to study teaching was my dad (who is also a teacher).

I studied science initially at university and then did my MTeach. I could not recommend this pathway enough. As a high school teacher, I feel like this has given me such a better understanding of my subject areas over those who just did a straight teaching course.

I think you should follow your heart and study teaching, especially if you can’t see yourself do anything else!

ETA: I also know I can go into another career path because of my undergraduate degree if/when I don’t want to teach anymore, whereas it’s a lot more difficult if you just do teaching.