PowerShell copy-item - powershell

Question

I am trying to copy latest 30days files to the folder by this code:
$month = (get-date).AddDays(-30).ToString("yyyMM")
$lastmonthfiles = Write-Host (-join('DCP_', $month,"*.csv"))
Copy-Item -Path Write-Host (-join ("C:\DC+\History\", $lastmonthfiles)) -Destination C:\DC+\History\Backup
but I am having a problem in path in copy-item instruction, which is
Copy-Item : A positional parameter cannot be found that accepts argument 'C:\DC+\History\'.
At line:5 char:1
+ Copy-Item -Path Write-Host (-join ("C:\DC+\History\", $lastmonthfiles ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidArgument: (:) [Copy-Item], ParameterBindingException
+ FullyQualifiedErrorId : PositionalParameterNotFound,Microsoft.PowerShell.Commands.CopyItemCommand
I am new in PowerShell, and programming so, I could not understand, how can I update and achieve a goal.

Answer 1

Try this:
$Source = Get-Item "C:\Games"
$Destination = "E:\Backup"
$LogFile = "C:\Copy-LogFile.txt"
Copy-Item -Path $( $Source | Where LastWriteTime -LE (Get-Date).AddDays(-30) ) -Destination $Destination -Recurse -PassThru |
Out-File $LogFile -Force
This takes care of your copy function and generates an output log.

Answer 2

Sorry, but your code makes no sense to me...
If it is your aim to copy files to a subfolder in a backup path, try this:
# get the date to use as subfolder to copy to and also to filter the last 30 days files
$refDate = (Get-Date).AddDays(-30).Date # .Date sets it to midnight
# set this variable to the folder where the csv are to be found
$sourceFolder = 'X:\Path\To\Where\The\Files\Are'
# create a destination path to copy to (just a string)
$destination = Join-Path -Path 'C:\DC+\History\Backup' -ChildPath ($refDate.ToString("yyyMM"))
# create this destination folder
$null = New-Item -Path $destination -ItemType Directory -Force
# get the files and copy them to the destination folder
Get-ChildItem -Path $sourceFolder -Filter '*.csv' -File | # filter on CSV fies only
Where-Object { $_.LastWriteTime -ge $refDate } | # filter on date 'last 30 days'
Copy-Item -Destination $destination -Force