If you have a dump file, then you can import the entire contents of the dump with the following command:
imp userid=system/manager file=my_dump.dmp log=imp.log full=yYou must sign on to the database with a user that has the privileges to create objects in other schemas, like the SYSTEM user. I log my import session to a log file so that I can review it for errors. The FULL=Y parameter will import the entire contents of the dump file.
Depending on how the dump file was created, you may have to create tablespaces and users before you import the contents of the dump file.