This is by design. Microsoft wants you online. But there are two reliable ways to bypass this. This method works for both Windows 11 Home and Pro (22H2, 23H2, and 24H2).
Published: [Date] Reading time: 4 minutes windows 11 install without internet
Start the installation as usual. When you reach the "Let’s connect you to a network" screen, do not connect to Wi-Fi . If you are on a desktop with an Ethernet cable, unplug it. This is by design