How to remove pages that are duplicated in the search?

Question

Google

Hello, I've run into this problem.
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Site pages in the search are displayed in two types (and some of them are duplicated):
1. https://www.name-site.com
2. https://name-site.com/
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I want to leave the second option - but how to remove the first without a clue.
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There is also a problem in the main page for some reason, it was indexed 2 times and in the second version it has the ending - https://name-site.com/?cgtz=169 - but I don't have such a label.

Answer 1

It is enough to put an explicit redirect from www on the web server. on without www.