plz guide me which processor i need to install for windows 11 in this system.
If you click the link above the message you posted it shows you supported processors. You just need to have one of them. The i7-7xxxx is a 7th gen Intel which isn't supported. The minimum processor is 8th gen for Intel i7 (with few exceptions) as discussed in that link the UI shows you. Refer to the docs to be sure the exact processor you're looking at is valid because some of the early processors that are 8th gen+ aren't supported because of perf/reliability issues.
For Windows 11, you can get any processor mentioned on this list:
Hope this helps!
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