Since Darknet is protected, it cannot be accessed directly.
The most popular way to access Darknet is by using TOR Browser / TOR Project
Technically, TOR stands for “The Onion Router” and using it is as simple as new browser.
After that you need a direct URL or the directory which contains URL of the websites. Only the URL ending with .onion extension are permitted.
Make sure while opening onion browsers you are using TOR Browser
Download it from here: https://www.torproject.org/