I do not see that option either in my version of DBeaver (6.1.3 - community). What you could do is initiate a restore with TSQL (by clicking on SQL Editor while you are connected to your database). Then in the Script area, use the below, modified for your own environment/database name.
USE [master] RESTORE DATABASE [DatabaseName] FROM
DISK = N'C:\FolderName\BackupName.bak' WITH FILE = 1, NOUNLOAD, REPLACE, STATS = 10
For full Tsql options to restore a database, see this: RESTORE Statements (Transact-SQL)