I need update for 6 plus

There are no more updates for the iPhone 6 Plus. It is too old. The last update was iOS 12.5.7

iOS 14 is no longer available. An iPhone 7 can run iOS 15.

An iPhone 8 or higher model can run iOS 16.

Also you will find that most App developers up-date their Apps for newer phones and drop support for older models.

Don't just toss it - you can recycle it at any Apple Store. Technology marches on!

No one said that you had to throw the iPhone 6. We said that you will need a newer phone if you want to run newer iOS versions.

You can probably sell the iPhone 6 for $40-50 on Ebay.