EXEC dbo.sp_BlitzFirst
     @OutputDatabaseName = 'tempdb'-- change here !!
    , @OutputSchemaName = 'dbo'
    , @OutputTableName = 'BlitzFirst'
    , @OutputTableNameFileStats = 'BlitzFirst_FileStats'
    , @OutputTableNamePerfmonStats = 'BlitzFirst_PerfmonStats'
    , @OutputTableNameWaitStats = 'BlitzFirst_WaitStats'
    , @OutputTableNameBlitzCache = 'BlitzCache'
    , @OutputServerName ='--YourServerName--'-- change here !!

$tableName = "BlitzFirst_FileStats"
      $query = "select * from [dbo].[BlitzFirst_FileStats]"
      $results = Invoke-DbaQuery -SqlInstance 'yourserverName,port' -SqlCredential $Cred -Database tempdb -Query $query
      $results = Write-DbaDataTable -SqlInstance 'yourTargetInstance,portNo' -SqlCredential $Cred -Database CentralDBName -Table BlitzFirst_FileStats -Schema dbo -AutoCreateTable