Does USPS print labels for you?

If you open an account on usps.com you can print your own labels and pay for postage. At the window in a post office, your package must already be addressed. They will sell you postage using the address you put on the mail. They do not have the ability to print the recipients address. All you need is a pen, since address labels are not required.
Read More

https://criminaljusticeclasses.net/does-usps-print-labels-for-you/