QR Codes are meant to make life easier --scan a code & get a direct link-- but if you don't have a QR reader installed on your phone, or can't easily find that one you downloaded a year ago, it can seem like a waste of time. By the time you download a QR reader from the app store and scan it, you could have just typed in the address.
Apple added a feature to their OS that make the QR reader as simple as promised-- the camera has a QR reader built in. Make sure it's enabled in your settings (pictured below), open your camera, and scan.
Settings --> Camera --> Scan QR Codes
(I am using iOS 12.1.1)