Requirements for complete recovery: All or damaged/missing datafiles, archive log files, online redo log files and control files.

Complete recovery involves using redo data or incremental backups combined with a backup of a database, tablespace, or datafile to update it to the most current point in time. It is called complete because Oracle applies all of the redo changes contained in the archived and online logs to the backup.

You can perform complete recovery on a database, tablespace, or datafile.

Steps to perform complete recovery on the whole database:

Restore a backup of the whole database or the files you want to recover
Mount the database
Ensure that all datafiles you want to recover are online
Apply online or archived redo logs, or a combination of the two

Steps to perform complete recovery on a tablespace or datafile, then you must:

Take the tablespace or datafile to be recovered offline if the database is open
Restore a backup of the datafiles you want to recover
Apply online or archived redo logs, or a combination of the two

STARTUP MOUNT;
RECOVER DATABASE;
ALTER DATABASE OPEN;

If not able to perform Complete Recovery then go to incomplete recovery/point in time recovery.

Note:
1. We can create a new control file if we know the locations of all data files and online redo log files.
2. We can create a new datafile and recover if we have all the archive log files from the beginning of adding datafile to the tablespace.