Hi Deoogee,
When you click REQUEST MEMBERSHIP that lets the club owner know you are interested in joining. If the club owner likes the idea of having you join up with them then he or she will send an invite to you which you will receive via the email that is listed on your account information. When you receive the invitation in your inbox you just have to click the link within to confirm the membership and join the club.
If you haven't heard anything or don't see anything in your email (or in your spam/junk) folders, you might want to get in contact with club owner. I'd also recommend checking your account information to make sure your email is listed properly and that you can receive emails from members@worldgolftour.com