I want to know, which attributes used while forming the BGP neighbor relationship.?

BGP attributes are used to condition the uplinnk and downlink traffic on an established BGP session .

To establish neighborship between 2 routers we need network layer reachability between 2 BGP speaking routers and we have to add each other router ID/address and AS number under BGP confi mode on each router .

Note : AS path attribute is not help here because it used in best path selection once BGP came up between to neighbor.

Your question is not that clear kindly provide the actual scenario to get your answer.