The video missed one small, but very important thing: You need to disable fast boot in windows before mounting your windows partition in linux, otherwise it will get corrupted.
The reason for that is that windows doesn't actually shut down if you tell it to by default and it leaves the drive in a dirty state. Windows itself can pick that back up and boot off of it, but linux won't detect it. If you leave fast boot on, windows will run chkdsk on the next boot after using linux.
I found that out the hard way and got to not use my computer while it ran chkdsk on my 4TB HDD. It took 15 hours.