The procedure requires some knowledge about JSON file format. Here is a brief
outline. Every member is represented as "name":"value" pair. Arrays use
square brackets and Objects use curly brackets. Read this Wikipedia: JSON
for more details.
Procedure:
- Open Windows Terminal. Click on the down arrow symbol ˅ from
menu bar. This will open a drop down menu from which select Settings option.
Alternatively use Ctrl + , to open Settings directly.
Here is a sample screenshot:

- After selecting the Settings, Notepad (or the default text editor) will open
profiles.json file. Here is a sample, see first JSON object i.e. "globals".
"globals" :
{
"alwaysShowTabs" : true,
"copyOnSelect" : false,
"defaultProfile" : "{12345678-1234-1234-1234-1234567890AB}",
"initialCols" : 120,
"initialRows" : 30,
We are interested in defaultProfile name. The value with 128-bit format
{12345678-1234-1234-1234-1234567890AB} is called UUID. Assume its like
a nickname for default shell :)
Now in that file, find "name" : "cmd" pair (or "commandline" : "cmd.exe" pair)
for Command Prompt. There will be a "guid" pair adjacent of it. Copy the value,
i.e. the 128-bit nickname. And paste it to globals > defaultProfile.
Restart Windows Terminal.
If you have installed Windows Terminal without Windows Store, the actual path
of the profiles.json is "%LocalAppData%\Microsoft\Windows Terminal\profiles.json".
You can directly open the path in any text editor.
Further Readings