to restoret he data without taking care of current db

USE [master]
ALTER DATABASE ForeSite_LS_s6 SET SINGLE_USER WITH ROLLBACK IMMEDIATE
GO
RESTORE DATABASE ForeSite_LS_s6 FROM DISK = 'E:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\Backup\ForeSite_LS_s6.bak'
WITH REPLACE
GO