If you would like to generate your own barcodes, there are many companies that specialize in printing barcodes.
If, however, you would like to generate barcodes yourself, you can use Microsoft Word or Google docs to do so.
Here's an overview of using Microsoft Word to generate barcodes: https://www.online-tech-tips.com/computer-tips/free-barcode-generator/
And here's an overview of using Google docs to generate barcodes: https://www.idautomation.com/barcode-components/google-docs-native-generator/user-manual.html