my version can't update plz help

This is the easiest way to check for updates and if one is even possible:

Update your iPhone, iPad, or iPod touch - https://support.apple.com/HT204204 - When you update you will only be given one update selection which will be the highest available iOS version supported by your device. If it says no update is available and you need a higher version you will have to buy newer equipment.

What iPhone model and what version iOS are you referring to?

Check the list in this link for the maximum version iOS your phone is capable of running: https://everyi.com/by-capability/maximum-supported-ios-version-for-ipod-iphone-ipad.html

If your phone is listed and it cannot go higher, what you do is buy a newer phone which can be updated.

What iPhone do you have? Is it too old to get an iOS update?

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