How to determine the progress of a SQL Server backup or restore process?

Please use below script

/****************************************/

SELECT

       session_id as SPID,

       command, a.text AS Query,

       start_time,

       percent_complete,

       dateadd(second,estimated_completion_time/1000, getdate()) as estimated_completion_time

FROM sys.dm_exec_requests r CROSS APPLY sys.dm_exec_sql_text(r.sql_handle) a

WHERE r.command in ('BACKUP DATABASE','RESTORE DATABASE')

/****************************************/

Screen shot where I have used this query