$FolderToBreak = "/sitename/Documents/testtt123"
$userToRemove = "user@domain.com"

##Variables for Processing
$SiteUrl = "https://sitename.sharepoint.com/sitename"
$UserName="globaladmin@domain.com.au"
$Password ="xxxxxx"

Add-Type -Path "c:CSOMMicrosoft.SharePoint.Client.dll"
Add-Type -Path "c:CSOMMicrosoft.SharePoint.Client.Runtime.dll"

#Setup Credentials to connect
$Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($UserName,(ConvertTo-SecureString $Password -AsPlainText -Force))

Try {
#Set up the context
$Context = New-Object Microsoft.SharePoint.Client.ClientContext($SiteUrl)
$Context.Credentials = $credentials

#Get the List Root Folder
$Folder=$Context.web.GetFolderByServerRelativeUrl($FolderToBreak)
#break inheritance just incase, should already be broken to share user to begin with
$Folder.ListItemAllFields.BreakRoleInheritance($true,$false)

#want to remove permission from the user $userToRemove from $folder but roleassignements doesnt have a .remove, and now i am lost....
$Folder.ListItemAllFields.RoleAssignments....

}
catch {
    write-host "Error: $($_.Exception.Message)" -foregroundcolor Red
}