“Microsoft will stop supporting Windows 7 beginning Tuesday, Jan. 14. That means it won’t issue any more software updates, including software patches that could prevent cyberattacks, to millions of computers.”
Learn more from this CNBC article or from the Microsoft official source
Howtogeek has a great article on how to upgrade to Windows 10.
https://www.howtogeek.com/272201/all-the-ways-you-can-still-get-windows-10-for-free/.