You haven't said what you are using to post with but if you have access to another computer, you can use that to create Win 10 install media using either a DVD or USB.
Read the instructions at
https://www.microsoft.com/en-gb/software-download/windows10After you have created the install media, tap F12 as you switch the on the affected machine and use the cursor keys to select the media option.
If using an USB then insert that before tapping F12, otherwise insert the DVD after selecting the DVD drive and press enter.
If using a DVD you will be momentarily prompted to press any key to boot from CD/DVD and when it loads, you may be presented with an inverse window with Windows Setup [EMS Enabled] highlighted - just press enter.
If using an USB, wait for it to load then change/confirm the Time and currency format then on the Install screen click on Repair your computer.
Select Troubleshoot/Advanced options and select Start-up Repair to see what that reports.
You could also try System Restore to see if a restore point will do the job.
If they fail to fix the boot problem then boot up with the install media again and navigate through Troubleshoot to select Command Prompt
Enter bcdedit |find "osdevice"
For clarity that is a Pipe symbol before find and is the uppercase of \
This will give you a partition letter where it sees the volume.
There are three cmds you can try to see if either will repair the corruption to boot normally.
Use your partition letter instead of the x I have exampled -
chkdsk x: /r
You can check the boot status after each of these cmds or just enter one after the other.
dism /image:x:\ /cleanup-image /restorehealth
It may mention something about a Scratch directory, but if the cmd completes then you can ignore that.
The third cmd is the following, again using your partition letter instead of the X I have exampled.
sfc /scannow /offbootdir=X:\ /offwindir=X:\Windows
Note the space before each / in all three cmds.
Let me know how you get on.