@AngieOttawa, aren't these last few days before the start fun. Just how many doubts can you pack-in to so few days
This time of year on the Norte pre-booking probably isn't essential and quite a few of the Albergues won't accept pre-bookings anyway. Of course local Hostales and Hotels will. You could give yourself some comfort by booking your first, and perhaps, second nights accommodation, where possible, by when you should have some feel for the road and the number of others you are walking with.
Dunno which guide you have because most seem to include, frequently misleading, elevation schematics.
www.gronze.com has reasonable illustrations but still not to scale. They might be a bit tricky to find. You have to click on the the button "Ver perfil de la Etapa" that sits just under the schematic route map.
This may, or may not, help but my attitude has always been that if I want to get from A to B and there is a hill in the way then it really doesn't matter how steep or how high that hill is. If I want to get from A to B and there is a hill in the way then I am going over it (or around it if I can
).
Finally, if your 'phone has GPS and you load an app such as maps.me then you don't need a local sim - But, if you want to be able to make occasional 'phonecalls, texts and send emails and pictures in Europe (I'm kind of guessing you are Canadian with that soubriquet) to the folks back home then there is loads of advice in the relevant sections of this forum which can be summed up as something like " go to an Orange/Vodaphone seller and buy a simple call/text/data package".
On the Norte? Follow the yellow arrows. They, and the kind-hearted people of Spain will get you to Santiago.