Hi and welcome to flying!
You'll do well to get one lesson a week, especially outside summer, given problems with the weather. Don't let that worry you, it's normal!
Don't worry about buying a headset before you qualify but, when you do, and if you can, buy a good noise cancelling set. Personally, I use Bose but there are many others and the choice is quite personal so, if you can, try before you buy.
Good luck with the course!
