There are several different types of QR Code generator. Many are provided on websites. Some are programs you can download on to you computer.
Here are some to try. (Remember, you use all external links at your own risk.)
If you need to generate QR Codes in bulk then you can either upload your links to a bulk online QR Code generator or install some software that does it for you locally. It’s worth noting that you can generate QR Codes from within Google Sheets.
To find out more about Google’s QR Code generator click this link which will trigger a Google search for you.