✌clearly explained. Very good video. The only point to add is once you had changed the name of the database you had forgot to change the entry in /etc/oratab with the new database name.
Yes, you can. Oracle Provides sample pfile in ORACLE_HOME directory. You can copy it and modify it as per your requirements. Also Password file can be re-created any time. You can restore your database even if you do not have pfile and password file. Its just more work.
I'm sorry but this is not a backup this is a transfer of the database to a seperate server. Why do I say this, first of all your rman files are stored on the original server. What will you do when your server bursts in to flames and you can't access the original server? Nothing, so you don't have a backup.
Very nice. Thanks for the comment. However, no organization would be storing backups on their original server. They will be stored on a storage disk which is different than the actual database server. And if they are storing the backups on database server itself, its a bad design. This video is a demo of how to perform backup and restore.