The Elevation PowerToys from Microsoft include a tool to open a PowerShell window in the current folder, among lots of other useful things. (I'm assuming there's no built-in way to do this, otherwise Microsoft wouldn't offer it as a download on their site.)
Once you've downloaded and extracted them, navigate to their folder, right-click on
PowerShellHere.inf and click Install. A PowerShell Prompt Here option will be added to the context menu of all directories and drives. You can also add context menu entries to open a PowerShell window with administrator privileges or as the
NT AUTHORITY\SYSTEM user.
Alternatively, if you don't want to install anything, you can just use the Open command window here option built-in to Windows and then run
powershell at the normal command prompt. A PowerShell session will open in the same command prompt window.