In Win11 when you right click the Start Button you see the Terminal app instead of Powershell or the Command Prompt like in Win10. And you have to do some digging or use search to find those two. In a way Terminal is the replacement for both.
Since Windows, Windows has used the same app or shell when you wanted/needed to use the command line or Powershell. That's changing with the Windows Terminal app, which will become the default in Win11 over the course of 2022 -- in Win10 both stable & preview versions are available in the store. It's unknown whether it will eventually become the default in Win10 -- while there are articles online showing how to make Windows Terminal the default in Win10, the settings they use are missing in Win10 20H1 & 20H2 today for both Terminal versions.
In Win11 *To me* the biggest advantage of the Terminal app is that you can open a Terminal window, and if it's running Powershell you can open a new tab showing the Command Prompt, and vice versa. In Win10 when you right click the Start Button you'll either see Powershell or the Command Prompt -- you set which one appears in Settings -> Personalization -> Taskbar -- and have to scroll to the bottom of the listed apps in the Start Menu to get to the other. [I have that right-click menu show Powershell, and have a desktop shortcut for the Command Prompt running as Admin. -- %windir%\system32\cmd.exe with the box for Run as Admin checked under Advanced in the shortcut properties.]
But I'm nowhere near a master, or even a mildly advanced novice when it comes to using the command line or Powershell -- when I need to use either I tend to copy/paste some command I found online. For those spending more time using either one, Terminal offers quite a few options including things like setting the colors and appearance.