Pls how do I download iOS 17 update

You cannot change the internal hardware in the iPhone.

To be able to run iOS15 or later, you need an newer iPhone

than the iPhone 6 you have.

You may wish to try going to Facebook via a web browser such as Safari.

An iPhone 5s, iPhone 6, or iPhone 6 Plus isn't capable of 13 or above; they require at least 2GB of RAM.

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