Where are you originally from? If it's SE Asia then be prepared for a shock when you get here.
As for Vancouver there are 2 big clubs, Op-For and BCAC (British Columbia Airsoft Club). They play at Panther Paintball I believe on a rotation (every second week). There are also other venues that are being looked into or they play at occasionally. Other venues include the "BigFoot field" that Fraser Valley Airsoft (FVA) plays at and some other venues.
Playing age is 16+ with parental waiver signed (no presigned waivers, parent must be present to sign), 18+ and you're good to go (sign your own waiver).
Sadly I haven't been out this year at all because of work and other weekend activities (my "home" team is based in Alberta though since I live there for 8 months of the year for school). So this is only from what I know of the airsoft scene in Vancouver but definitely think of joining the local clubs and introducing yourself when you get here (if not here already).
PS: The places for surplus are Daves Army Surplus (DSTactical) in New West and PoCo Surplus (2 locations, one in Port Coquitlam and a new one in Langley). Sorry if I've missed out any other great surplus shops but those are the two that come to mind first.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE