Freezing and Unfreezing multiple users or how to avoid multiple users logging into Salesforce

 IsFrozen in UserLogin is used for Freeze or unfreeze.

So, fetch the UserLogin records and mass update.

Referene Link - https://help.salesforce.com/articleView?id=000337702&language=en_US&type=1&mode=1

 

Data Loader can be used for Export and Import.