If you don't have a printer, you can take your package to a local UPS Store. They can help you create the label and print it for you, often for a small service fee.
If you are looking for physical, blank labels or specific carrier stickers to use with your own printer, you can find them from various retailers: Create and Print Shipping Labels | UPS - United States buy a shipping label ups
When you buy a label online, UPS often provides a mobile UPS Shipping QR code. You can show this at a UPS Store, and they will print the label for you on-site. UPS Shipping Supplies & Physical Labels When you buy a label online, UPS often