This is probably the best starting point for understanding how to build the “QR code library” part of your question: https://www.nayuki.io/page/creating-a-qr-co

This is probably the best starting point for understanding how to build the “QR code library” part of your question: https://www.nayuki.io/page/creating-a-qr-code-step-by-step https://www.nayuki.io/page/creating-a-qr-code-step-by-step