Why my system isn't coming up

I am not too sure what you mean by "level of the 4 windows stage" but try possible solutions below:

Accessing Advanced Start‐up when PC isn't loading:

If your device isn't loading or stuck during boot, you can use this method to access the recovery environment:

1.       Turn on your PC.

2.       As soon as the Windows logo appears, press the power button to turn off computer.

3.       Repeat steps 1 or 2 two more times.

After the third interruption, Windows 10 will open into the Advanced Start‐up environment

While in the Advanced start‐up environment, use the following steps to use Start‐up Repair:

1.       Click the Troubleshoot button.

2.       Click the Advanced options button.

3.       Click the “Start‐up Repair” button.

4.       Select your account.

5.       Type your account password.

6.       Click the Continue button.

If the above doesn’t help do the same as above but this time select “System Restore” from the

“Advanced Options?”

Or from an installation disk/flash drive

1.      Boot from the the installation media for the installed version of Windows.

2.      On the Install Windows screen, select Next > Repair your computer.

3.      On the Choose an option screen, select Troubleshoot.

4.      On the Advanced options screen, select Startup Repair.