I want to connect Bluetooth in a circular ring is it possible to contect 8 arduino with each other via Bluetooth hc05 or hc06 and share data into tha ring..
Its probably possible, but I don't think it would be a good idea.
Each Arduino is going to have to forward information it receives that is not for it. This is a drain on processing power. Add to that you are going to need to give the devices an identity, so they know what data is for them, and a inform them of the topology of the network so they know how to connect to the adjacent nodes.
Depending on what problem you are trying to solve you might want to look at direct radio coms implementing a mesh network, or the simplest of all solutions Wifi. You could use an ESP8266 to form an access point and others to connect to it. I believe there might be a limit to the number of connections an ESP8266 can have at any one time but this could be mitigated by dropping the connection after the message has been sent.