Microsoft supports its operating systems for only a fixed period of time after that version is replaced. For Windows 7 support ends in January 2020.
Why does it matter?
Microsoft will no longer provide bug fixes or security updates. And no longer provide technical support. Continuing to use Windows 7 after that date thus carries a higher risk of security problems and software incompatibility problems. About 40% of PC’s still use Windows 7, so a lot of computers need to be updated.
What do you need to do about it?
January 2020 sounds like it is a long way away, but it takes time to consider the options, make a plan, and implement it. Is a hardware upgrade due as well, making it easier just to replace computers? Is the best approach to upgrade existing hardware to Windows 10? If you have software that does not work on Windows 10, can it be replaced or upgraded?
If all else fails, Microsoft will provide support to business users of Windows 7, but that comes with a price that goes up every year.