Here's a quick demonstration to showcase how to hide your products from onsite (your Shopify website) and offsite (Google Search, Bing, Duck Duck Go, and other search engines) search. This technique requires zero coding and leverages a hidden SEO metafield that has been around for a long time, but is really hard to find in documentation. It removes products from the sitemap, which effectively makes it "invisible" to onsite and offsite search.
More information about the hidden from SEO metafield here: https://shopify.dev/docs/apps/build/marketing-analytics/optimize-storefront-seo#step-2-hide-a-resource-from-search-engines-and-sitemaps
In this video, we also look at how to update and remove these products from automated collections, including the All products collection Shopify creates automatically.