In the next settings, you need to select a channel for the Windows Insider program, here you can select Dev Channel.You will need to add your Microsoft account.Click the Get started button and enroll in the Windows insider program.At the bottom, you can see the Windows Insider Program option, select this option.Click on Update & Security from the list.In order to join the insider program, open the settings panel and follow the instructions below. In case your PC is not meeting the criteria, you will not be able to join the Windows 11 Insider program as of now. In this case, you can still join the program and get the Windows 11 Preview build if your PC is meeting the criteria. You can go ahead and start downloading the Insider Preview build from the settings.
But do note that if you install Windows 11 on PCs not meeting the hardware requirements, there are chances of crashes happening. Since you are already in the Insider program before June 24th, Microsoft will allow you to install Windows 11 even though your PC may not be meeting the minimum specs requirement for Windows 11. If you are already in the Windows Insider Program, then Microsoft has detailed the eligibility criteria to get the Windows 11 Insider preview build.