Yes, I am using a computer with Windows 10.
What are you buying? I've had this computer for 6 years. Haven't purchased anything at all except a mouse. If this one lasts another 2-3 years, I will buy a new one then.
The internet continues to get more sophisticated that over time the current operating systems and your computer may no longer support it. Then, they must update or come out with something new or you must buy a new computer to keep up with it.
So far, Microsoft is still supporting and updating 10, so you should be OK for some time yet if you are using that. Windows 11 should be around for a long time.