To restore follow below commands which is a sample you have to replace site url and backup file name which is highlighted in bold. You may be required to put root password.
cd ..
cd home
cd frappe
cd frappe-bench
bench use ctpcdemo.powersoftsystem.com
bench restore /home/frappe/frappe-bench/sites/ctpcdemo.powersoftsystem.com/private/backups/ABC.sql.gz
Note system may prompt for mysql root password then you need to check
the account deails of the customer for the same