Docs: Add docs for `Explore topics` page

doc/user/admin_area/index.md

@@ -241,8 +241,8 @@ To [Create a new group](../group/index.md#create-a-group) click **New group**.
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/340920) in GitLab 14.4.
 
-You can administer all [topics](../project/settings/index.md#topics) in the GitLab instance from the
-Admin Area's Topics page.
+You can administer all [topics](../project/working_with_projects.md#explore-topics) in the 
+GitLab instance from the Admin Area's Topics page.
 
 To access the Topics page:
 

doc/user/project/settings/index.md

@@ -43,7 +43,7 @@ To assign topics to a project:
 1. Under **Topics**, enter the project topics. Existing popular topics are suggested as you type.
 1. Select **Save changes**.
 
-For GitLab.com, explore popular topics on the [Explore topics page](https://gitlab.com/explore/projects/topics).
+For GitLab.com, explore popular topics on the [Explore topics page](../working_with_projects.md#explore-topics).
 When you select a topic, you can see relevant projects.
 
 NOTE:

doc/user/project/working_with_projects.md

@@ -13,7 +13,7 @@ code are saved in projects, and most features are in the scope of projects.
 
 You can explore other popular projects available on GitLab. To explore projects:
 
-1. On the top bar, select **Menu > Project**.
+1. On the top bar, select **Menu > Projects**.
 1. Select **Explore projects**.
 
 GitLab displays a list of projects, sorted by last updated date. To view
@@ -25,6 +25,21 @@ By default, `/explore` is visible to unauthenticated users. However, if the
 [**Public** visibility level](../admin_area/settings/visibility_and_access_controls.md#restrict-visibility-levels)
 is restricted, `/explore` is visible only to signed-in users.
 
+## Explore topics
+
+You can explore popular project topics available on GitLab. To explore project topics:
+
+1. On the top bar, select **Menu > Projects**.
+1. Select **Explore topics**.
+
+GitLab displays a list of topics sorted by the number of associated projects.
+To view projects associated with a topic, select a topic from the list.
+
+You can assign topics to a project on the [Project Settings page](settings/index.md#topics).
+
+If you're an instance administrator, you can administer all project topics from the
+[Admin Area's Topics page](../admin_area/index.md#administering-topics).
+
 ## Create a project
 
 To create a project in GitLab:
@@ -213,7 +228,7 @@ To star a project:
 
 To view your starred projects:
 
-1. On the top bar, select **Menu > Project**.
+1. On the top bar, select **Menu > Projects**.
 1. Select **Starred Projects**.
 1. GitLab displays information about your starred projects, including: