You have to turn off "Fast Startup" mode (which is, in reality, a slow startup mode).
Steps here:
https://www.tenforums.com/tutorials/4189-turn-off-fast-startup-windows-10-a.html
EDIT:
Short Version
Look for Power Options => System Settings then at the bottom of the window there is an insert "Shudown settings" where you have to uncheck the "Turn on fast startup" option.
How to Turn On or Off Fast Startup in Windows 10
Open the Control Panel (icons view), and click on the Power Options icon.
Click/tap on the Choose what the power buttons do link on the left side. (see screenshot 1 below)
screenshot 1
- Click/tap on the Change settings that are currently unavailable link at the top. (see screenshot 2 below)
screenshot 2
If prompted by UAC, click/tap on Yes.
Do step 6 or step 7 below for what you would like to do.
To Turn On Fast Startup
(This is the default setting) Under Shutdown settings, check the Turn on fast startup box, click/tap on the Save changes button, and go to step 8 below. (see screenshot 3 below step 8)
- To Turn Off Fast Startup
Under Shutdown settings, uncheck the Turn on fast startup box, click/tap on the Save changes button, and go to step 8 below. (see screenshot below step 8)
- You can now close the System Settings window if you like.
screaanshot 3
If the Turn on fast startup setting is not listed, then you will need to close the System Settings window, enable hibernate, then start over at step 1 again.
More info
The "Fast Startup" is a sort of hibernation mode, so if you power off your computer when lot's of programs are running / are open windows try to restore everything which involve lot's of read from your hard drive and can be long.