Kosta, don't worry I know you are trying and will be here to help as much as you need. I am traveling now so may be out of touch for hours at a time but I will check in on you several times a day.
Did you confirm UEFI is enabled in BIOS? Are you able to set Windows Boot Manager first in Boot Priority?
Then boot the media from the BIOS Boot menu key I give in the tutorial here: BIOS Boot Menu Key
I show you exactly how to trigger it by powering on the PC while pressing the key.
Then proceed with the written steps to skip Product Key, choose Install Now, Custom Install then delete all partitions off the drive, choose the resulting Unallocated Space and click Next to auto-create and format the needed partitions and begin install - this makes it foolproof.
The problem with setting the flash stick installer first to boot in BIOS Setup is that it will cause the install to start over again when it restarts during install. You can avoid this by unplugging the flash stick before it restarts.
After install expedite all Windows Updates including Optional until no more are offered. Then import any drivers from the PC maker's Support Downloads web page for your model that are newer, or branded instead of generic. The most basic thing we need to learn to maintain a PC is how to keep the latest manufacturer's drivers current. Windows drivers are rarely enough.
Please let me know if the tutorial is not understandable and perhaps needs translation.
Keep me posted on your progress as I will be here to help until the case is resolved.