FAQ : What is SQL Server PRINT equivalent in Oracle

Print In SQL Server
Returns a user-defined message to the client. Mainly Print is used while debugging procedures or triggers.
Eg
PRINT N'This is from first Loop.';

Oracle Equivalent :
What can come close in Oracle is DBMS_OUTPUT.PUT_LINE. Dbms_output is a PL/SQL Package which has a put_line procedure which write data to flat file or to direct your PL/SQL output to a screen.

DBMS_OUTPUT.PUT_LINE ('This is from first Loop);