Based on original article found here: https://www.tenforums.com/tutorials/6917-change-account-type-windows-10-a.html#option4
To Change a User's Account Type in Command Prompt
1. Open an elevated command prompt.
2. Do step 3 (see current type), step 4 (guest), step 5 (standard user), step 6 (administrator), or step 7 (remove) below for what you would like to do.
3. To See Current Account Type of Users