For how long will it be possible to get Windows 7 when buying a new computer

Main problem: new Intel processor comes with new graphics engine ... no driver for Windows 7 available.
All new hardware with current Intel processor/chipset will have this problem.

What about my current Windows 7 installation, can I continue using that for an undefinite time?

I could see now that all new computers come with Windows 10.

Ramin,

so I can use my current Windows 7 without problems until 2010 then?

My good reason is I have an electronic dictionary software with technical dictionaries installed which do not work on Windows 10 (and can not be modified to work with Windows 10). This software company cancelled their agreement with the publisher of the dictionaries.

John Tsioumpris,

do you mean I can build a VM with Windows 7 on a new computer with Windows 10?

yes, according to this page on Microsoft Support:
https://support.microsoft.com/en-us/help/13853/windows-lifecycle-fact-sheet

You can use Windows 7 to  January 14, 2020 but this doesn't mean you can install it on new hardware sine like you know now new hardware will not going to be compatible with W7.

Nobody forces you to use Windows 10. You can use Linux on machines that windows 7 cannot support.

What about using my dictionary software with help of Linux (if Linux can run Windows 7)?

If your old harddrive working you can still connect it to new computer.
If you lucky then windows will start in safe mode with networking, then you can try installing network adapter to get internet access and try update all drivers.

Maybe you'll get lucky

Thanks for the suggestions, a Windows 7 in a VM seems like the best solution.