How do I set up the connection between the Toad and Oracle 11g.Can you please help me with the contents of Tnsname.ORA and Listner files
You’re going to need to get that information from your DBA, or the person who installed the database.
Alternatively, there are sites like this one that can bootstrap you to setting up your TNSNAMES file. Hope this helps.
The syntax for tnsnames.ora is as follows:
network_service=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
(CONNECT_DATA=
(SERVICE_NAME=)))
and is listed at
https://docs.oracle.com/cd/B28359_01/network.111/b28317/tnsnames.htm#NETRF260