WordPress .Com .Org Confusion

I have a website http://www.dbl07.co/
It came with a blog ie post etc.
I have another blog with wordpress.com that I want to be the default blog attached to my website above. It is https://webdesigncolumbiasc.wordpress.com

So, I’m guessing there is a setting somewhere that will make this happen, I just don’t know if it’s on the wordpress.com or wordpress.org aka my website/wp-admin login side. Any thoughts?
Thanks!