mixz1
Typically, the device OEM will automatically maintain/upgrade the device OS (OEM flavor of Android) and OEM apps… until the device is no longer eligible for updates. If you are lucky, a new device will get one or two Android OS updates… a cheap device maybe none… this should be stated in the device specs and can influence the decision to buy it in the first place since everyone wants their device to remain current, usable, and secure for as long as possible.
tldr: Just use it until it stops working.
OE