How to scan a Twitter QR code?

okay so here is twitter so to scan a qr code just tap on your profile on top left and tap on um qr code here and then you it's generated but you can also scan it so scan qr code to easily follow an account and you can also upload from the picture so for example you can just have a saved picture and then you can just upload from your photo library and then just how you scan your qr code on twitter