Hello @Siva Karthik ,
Check if this works;
Type "winver" in cmd, if your version is Windows 10 21H2. Go to Windows Update, Scroll Down, and become a Windows Insider. Now choose 'Beta Channel', after you install Windows 11, choose 'Release Preview Channel'. After all, go to Windows Update again, and Check for Updates. You will see that there is a Feature or an Optional update for Windows 11. Download it. It will take 1-2 hours to install depending on your Computer...!
Thank you,
Desandu Hettiarachchi