The Availability Groups feature on Windows requires a Windows Server OS because it depends on Windows Server Failover Clustering (WSFC). This and other prerequisites are detailed in Prerequisites, Restrictions, and Recommendations for Always On availability groups.
You can, however, create Windows Server VMs on Windows 11 for testing AGs as long as your machine has virtualization capabilities. A basic setup for a stand-alone lab would consist of a domain controller VM and 2 Windows Server VMs for AG cluster host nodes, each with SQL Server Developer Edition installed.