Hi, Sandeep,
1. no, you do not need to install Blue Prism on the server where you are installing Decipher. But then you need to create a new user in RabbitMQ as the default user guest/guest is not allowed to connect from another machine than localhost.
2. it depends whether you installed sqlexpress or full sql server. If full sql server then only sqlserver name is sufficient. If sqlexpress then you need server\sqlexpress. Furthermore it depends whether Decipher runs on the same machine or different one. When it is running on different machine do not forget to enable TCP/IP, SQL Browser (for sqlexpress it is disabled by default) and in case you are running with firewalls enable 1433 TCP and 1434 UDP ports.
Regards,
Zdenek