Does the theme change in the Dashboard of WordPress have an impact on the site itself? If I change and activate other theme I want.
Yes, activating a theme will change your live site.
does the change of theme have a negative influence on Google’s search results
We’d need a crystal ball for that, but seriously, yes because search engines are robots that read the HTML of a page. The HTML changes for each theme because every theme is unique in some way. Whether that changes for the better or worse is not something we can answer.
]]>Yes, but I specified I will not change permalinks in WordPress but even so have an impact due of changes of a theme in search results?
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