The doubt:You are taking cold backup, So the mentioned procedure you can follow. But ensure all the services/background processes related to database are not running.
1. is this plan ok for refresh of the test databases?
2. with the backup taken at step1 and standby ctl file created at step 5 can i create a physical standby database of the testing db?
Please note, the production database is only in picture while taking backup.
6.open the database.Once you open the backup, it diverges from the primary. You can't use this opened database to build a standby for the primary.