Add-Type -Path "C:Program FilesCommon Filesmicrosoft sharedWeb Server Extensions16ISAPIMicrosoft.SharePoint.Client.dll"
Add-Type -Path "C:Program FilesCommon Filesmicrosoft sharedWeb Server Extensions16ISAPIMicrosoft.SharePoint.Client.Runtime.dll"

$siteUrl = "https://mysiteURL"

$ctx = new-object Microsoft.SharePoint.Client.ClientContext($siteUrl)

$web = $ctx.Web
$list = $web.Lists.GetByTitle("GENERAL DOCUMENTS")
#$ctx.Load($list)
$ctx.Load()

$ctx.ExecuteQuery()

$listroleassignments = $list.RoleAssignments
$ctx.Load($listroleassignments)
$ctx.ExecuteQuery()

foreach($listroleassgnment in $listroleassignments)
{
$ctx.Load($listroleassgnment.Member)
$ctx.Load($listroleassgnment.RoleDefinitionBindings)
$ctx.ExecuteQuery()

foreach($listroledefinition in $listroleassgnment.RoleDefinitionBindings)
{
$ctx.Load($listroledefinition)
$ctx.ExecuteQuery()
Write-Host -ForegroundColor Green $listroleassgnment.Member.Title: $listroledefinition.Name
}
}

Add-Type -Path "C:Program FilesCommon Filesmicrosoft sharedWeb Server Extensions16ISAPIMicrosoft.SharePoint.Client.dll"
Add-Type -Path "C:Program FilesCommon Filesmicrosoft sharedWeb Server Extensions16ISAPIMicrosoft.SharePoint.Client.Runtime.dll"
cls

$username = "user@company.onmicrosoft.com"
$password = ConvertTo-SecureString "pwd" -AsPlainText -Force

$siteUrl = [string]::Format("https://company.sharepoint.com")
$ctx = New-Object Microsoft.SharePoint.Client.ClientContext($siteUrl)
$ctx.Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($username, $password)

function GetPermission($Web,$ctx)
{
    # Root Web
    $Web = $ctx.Web
    $WebRAs = $Web.RoleAssignments
    $ctx.Load($Web)
    $ctx.Load($WebRAs)
    $ctx.ExecuteQuery()

    Write-Host $Web.Url -ForegroundColor Cyan

    foreach($WebRA in $WebRAs)
    {
        $ctx.Load($WebRA.Member)
        $ctx.Load($WebRA.RoleDefinitionBindings)
        $ctx.ExecuteQuery()

        foreach($WebDB in $WebRA.RoleDefinitionBindings)
        {
            $ctx.Load($WebDB)
            $ctx.ExecuteQuery()
            Write-Host -ForegroundColor Green $WebRA.Member.Title: $WebDB.Name
        }
    }

    # Root Lists
    $Lists = $Web.Lists
    $ctx.Load($Lists)
    $ctx.ExecuteQuery()

    foreach($List in $Lists)
    {
        $ctx.Load($List)
        Write-Host $List.Title -ForegroundColor Yellow
        $ListRAs = $List.RoleAssignments
        $ctx.ExecuteQuery()
        $ctx.Load($ListRAs)
        $ctx.ExecuteQuery()

        foreach($ListRA in $ListRAs)
        {
            $ctx.Load($ListRA.Member)
            $ctx.Load($ListRA.RoleDefinitionBindings)
            $ctx.ExecuteQuery()

            foreach($ListRD in $ListRA.RoleDefinitionBindings)
            {
                $ctx.Load($ListRD)
                $ctx.ExecuteQuery()
                Write-Host -ForegroundColor Green $ListRA.Member.Title: $ListRD.Name
            }

            #Here can be added $List.Items in same way
        }
    }
}

GetPermission -Web $siteUrl -ctx $ctx

# Sub Webs
$ctx.Load($Web.Webs)
$ctx.ExecuteQuery()

foreach($Web in $Webs)
{
    GetPermission -Web $Web -ctx $ctx
}