The Internet is often depicted as an iceberg, in which the visible part is popular websites, social networks, and all information is indexed by search engines. The underwater part is the Deep Web. This part of the network is not visible to a normal user. Access to private forums and chats, information banks is closed, including to search engines. And even lower is the very Darknet, being the bottom of the information "iceberg".
Its domains cannot be opened in a regular browser, the address can generally be a random set of characters or a cipher. To access the shadow part of the Internet, you will need special software. The easiest option is to use the Tor browser.
The dark web, like the regular Internet, uses domains (for example, .onion or .i2p), but sites with such domains cannot be accessed using the regular web and standard browsers Chrome, Internet Explorer or Safari, etc. It is not uncommon for a dark web URL to use a random character set or cipher. For example, the site: facebookcorewwwi.onion is a mirror of the Facebook social network in the dark web. The address cannot be opened in a normal browser.
Darknet sites are indexed by search engines, but this, of course, is not the usual Google or Yandex.
I am sure that it will be useful for you to read how to access darknet if this topic is close to you. I wish you good luck