There are three approaches to sharing data between environments, in order from safest to riskiest:
Use the database backup feature to backup your production database and then manually restore it to the staging database. This is the safest alternative, as you're not working directly with your production database.
Set up a master/replica database on the production environment and connect to the replica from the staging environment.
Share your production database with the staging application, which would allow read/write access to the database from your staging enviroment. In this scenario, we strongly urge you to plan for how you will avoid writing test or junk data to your production database.