Here is the link to register players, coaches and referees.

https://system.gotsport.com/programs/6395093R3

Your player will play based on his/her birth year.

Age Matrix
U16 2007-2008
U14 2009-20010
U12 2011-2012
U10 2013-2014
U8 2015-2016
U6 2017-2018