Not only does Windows not boot from USB (disregarding hacks and the OTG version) you also discover issues with drivers and it's such a lot of work that the answer is no. You won't do this.
As to corrupt the OS, Windows 10 is no different about backups. And with the new WCRY Global breakout backups are again, no longer optional.
Pick the article you want from https://www.google.com/search?q=how+to+move+old+font+files+to+Windows+10&ie=utf-8&oe=utf-8 but my choice would be to install the Cricut software first and the fonts again to get a fresh start.
The SVG files are your projects as far as I can tell and you place those as you wish in the user's folders.
My wife's 7 year old computer crashed on her. We believe it was the mother board due to power issues. Instead of having it repaired she just purchased a new computer.
Her hobby is Cricuting. Therefore she has hundreds of different fonts and SVG files stored on the old computer HDD. I made her old HDD into a USB HDD in hopes of being able to transfer those fonts onto her Windows 10 system. I want to be able to do this safely of course as to not corrupt the Win 10 OS.
Can anyone please tell me the steps to this process? If it is possible that is. If not, is it safe to boot the new computer up using the old HDD and if so, How do I go about doing that?
She loves doing this Cricuting hobby but has invested a bit of money in these fonts and SVG files, and she doesn't want to have to buy them all again.
Thank you in advance for any help.

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