PowerShell function to create Graph Access Token

Get-GraphToken.ps1

function Get-GraphToken {
        [cmdletbinding()]
        Param(
            [Parameter(Mandatory = $True)]
            [String[]]
            [ValidateSet("MSGraph", "Azure", "Monitor", "MSPIM")]
            $Client,    
            
            [Parameter(Mandatory = $False)]
            [String]$Resource = "https://graph.microsoft.com"   
        )

        switch ($Client) {
            "MSGraph" {
                $body = @{
                    "client_id" = "d3590ed6-52b3-4102-aeff-aad2292ab01c"
                    "resource"  = "https://graph.microsoft.com/"
                    "scope"     = "CrossTenantInformation.ReadBasic.All"
                }
            }
            "Azure" {
                $body = @{
                    "client_id" = "d3590ed6-52b3-4102-aeff-aad2292ab01c"
                    "resource"  = "https://management.core.windows.net"
                }
            }
            "Monitor" {
                $body = @{
                    "client_id" = "d3590ed6-52b3-4102-aeff-aad2292ab01c"
                    "resource"  = "https://monitor.azure.com/"
                }
            }
            "MSPIM" {
                $body = @{
                    "client_id" = "d3590ed6-52b3-4102-aeff-aad2292ab01c"
                    "resource"  = "https://api.azrbac.mspim.azure.com"
                }
            }
        }

        # Login Process
        $authResponse = Invoke-RestMethod `
            -UseBasicParsing `
            -Method Post `
            -Uri "https://login.microsoftonline.com/common/oauth2/devicecode?api-version=1.0" `
            -Body $body
        
        Write-Output $authResponse.message
        $continue = $true
        
        $body = @{
            "client_id"  = "d3590ed6-52b3-4102-aeff-aad2292ab01c"
            "grant_type" = "urn:ietf:params:oauth:grant-type:device_code"
            "code"       = $authResponse.device_code 
        }
        while ($continue) {
            Start-Sleep -Seconds $authResponse.interval
            $total += $authResponse.interval

            if ($total -gt ($authResponse.expires_in)) {
                Write-Error "Timeout occurred"
                return
            }          
            try {
                $global:graphToken = Invoke-RestMethod `
                    -UseBasicParsing `
                    -Method Post `
                    -Uri "https://login.microsoftonline.com/common/oauth2/token?api-version=1.0 " `
                    -Body $body `
                    -ErrorAction SilentlyContinue
            }
            catch {
                $details = $_.ErrorDetails.Message | ConvertFrom-Json
                $continue = $details.error -eq "authorization_pending"
                Write-Output "Waiting for approval: $($continue)"

                if (!$continue) {
                    Write-Error $details.error_description
                    return
                }
            }
            if($graphToken) {
                break
            }
        }
    }

Added option to request access token for MS-PIM endpoint