This article explains the three different ways to open the emoji keyboard and switch to character view for additional symbols.
How to Use an Emoji Keyboard on a Mac
As a Mac user, you know that your Mac menu bar contains actions for Finder, along with the app you’re currently using. This makes the menu bar the easiest place to remember how to access the emoji keyboard.
Select Edit and choose Emoji & Symbols.
Then you will see the happy smileys, people and animals appear in a small window.