no w7, go for w10 ltsc instead
Use Windows 10 LTSC 1809 instead. This version does not have windows store or any other sponsored applications. Not to mention that the most of telemetry stuff can also be disabled.
About the boot issue, if the system came preloaded with windows from the factory it may be installed in UEFI mode therefore your new bootable media also has to be UEFI compatible. (Use rufus) However, if you already have "legacy" bootable media that does NOT support UEFI boot, go into bios and then to "boot" section and turn on "csm" or "legacy" support. This might introduce some problems down the line as UEFI and Legacy BIOS use different partition tables (gpt and mbr respectively)
If you're interested in 1809 Enterprise LTSC, I can provide download links and help create UEFI compatible media. It's not that hard, trust me.
Oh and by the way, NEVER go down the Windows 7 route because its support has just ended and will be vulnerable to viruses in the future. Furthermore, assuming you have a notebook that come with 7th gen or newer intel CPU, windows 7 is straight away unsupported and no drivers are available either. Might require bit more tinkering to get the mouse and keyboard work during the setup (due to w7 not having usb3 drivers to boot, can inject these files into the bootable media though)
*EDIT2* added links to download
w10 ltsc direct:
mega link for both 32 & 64, can download separately
w10 ltsc torent (magnet): magnet:?xt=urn:btih:527ED958E7B901B78BC260DD0BB7364C71D7D403
w10 ltsc direct (mirror):
multi-lang. use "en" for english
Password is "LostED" (without quotes) if necessary.
rufus:
download
detailed guide on the process
activator. use kms38 option
