with your wind conditions and weight it is a tough call.
First,if you for sure see yourself as a kiter, think long term...
vast majority of us have 3 or even more kites for varying wind conditions.
and 2 or more boards,But i am not saying run out and buy a buncha gear...
think how your first kite will match-up with your potential quiver of kites..
7-10-13.....9-12-15.....8-11-14 for example.
For learning i always recommend slightly smaller kite,it will make you fly the kite
more,and hone kite flying skills,and more useful if the wind picks up.
This is where it becomes tricky with your light wind conditions.
First- does it ever blow more than 10-15 were you are?
If VERY rarely,and with your weight,you may consider a 12M
if you occasionally you get stronger wind,get a 10M.
something makes me reluctant to recommend a 12M as a first kite for a girl.
thats where your local wind conditions dictate.
Boards-A bigger board will accelerate learning.
when i say bigger,width is more useful than length 132 - 40 Length X 42 - 46 Width range
Usually,think that your first board will get outgrown,but will remain useful as
a light-wind board,but sounds like all you get is light wind ?
I like a 10M and a bigger 135x43-ish board really any brand,less than
3-4 years old for you to start out with....
then down the road,get the board you love