Need some information on process Purging and archiving

1. Is Purging and archiving process can be triggered by only ticking Enable archiving on case type ?

2. Where does the zip files got saved in the process ?

3. Can we restore the files to the same environment  which has generated through Purging and archiving process ?

4.Is Purging only possible without archiving ?

5. What are the tables that needs to be tested whether the Purging and archiving process ran successfully ?

5. If a application needs to be decommissioned from a single instance where there are few more applications is Purging and archiving process recommended ?