How to create an email script and set an alarm to it in PowerShell?

I’m making a PowerShell program that involves having a pop-up box appearing at a specific time, while the script is running and when the alarm goes off, alert box will show up onto the screen. For the alarm below, I want it to not only to pop-up, but I want to send an email message after exiting the pop-up. How would I do that?

function New-Alarm
{
param(
[Parameter(Mandatory=$true,HelpMessage=“Enter a time in HH:MM format (e.g. 23:00)”)]
[String]
$time,

[Parameter(Mandatory=$true,HelpMessage="Enter the alert box title (e.g. Alert!).")]
[String]
$alertBoxTitle,

[Parameter(Mandatory=$true,HelpMessage="Enter the alert message.")]
[String]
$alertBoxMessage

)

do
{
Start-Sleep -Seconds 1
}
until((get-date) -ge (get-date $time))

Play system sound:

Display message

}

New-Alarm -time “12:00” -alertBoxTitle “Alert!” -alertBoxMessage “Send an E-Mail to someone”

I want the email script right here after “Send an E-Mail to someone” pops up onto the screen.

Use the Send-MailMessage cmdlet.

Can you show me how to do that? I want to use Gmail to send the message to the receiver.