If you need to hide pages from Google, use the right tool for the job. Add a...

https://www.jelly-bookmarks.win/want-to-clean-up-your-search-results-use-a-noindex-tag-in-your-page-header-to

If you need to hide pages from Google, use the right tool for the job. Add a "noindex" meta tag to tell crawlers to drop the page from results. If the content is gone forever, return a 404 or 410 status code