How do you sent a receipted email to someone? So we known they recieved the email we sent them?

It's part of the headers of an email. Headers are things which describe to an email client what to do with an email. To put these things in the headers, you need an email client which does it for you. Outlook will do, as will many other email clients. A lot of web email clients won't do it.

One thing to note: often the "receiving" email client is asked whether they want to acknowledge the receipt. They can easily read your message without sending a receipt if they so choose. On that same score, asking for a read receipt is often seen as rude these days.