After having a rummage around on Google, I think Option 5 in this article should help you to move onto creating other accounts with the hidden admin account.
https://www.tenforums.com/tutorials/2969-enable-disable-elevated-administrator-account-windows-10-a.html#option4When you first get to the Command Prompt, enter
bcdedit |find "osdevice" and that will tell you the partition it sees the volume it is using as in that mode, it doesn't always see it in C: as the article points out.
For clarity, that is a Pipe symbol before
find and is the uppercase of \
I don't know what you are using to post on but if you have access to another computer with the same 32 or 64 bit architecture, you can create Win 10 install media by following the instructions in
https://www.microsoft.com/en-gb/software-download/windows10If you don't already have your computer set to boot from a DVD or USB before the HDD then you can change the boot order in the BIOS by pressing and holding F2 as you switch on.
Use your cursor keys to move along to Boot then again to select the media you want it to check first and use F5 or F6 to move it to the top.
Insert the install media then press F10 to Save and Exit - press enter to confirm.
If you using a DVD you will be prompted for a few seconds to press any key to boot from CD/DVD and then wait for it to load.
Click on Troubleshoot - Command Prompt and then follow the tutorial.