I’m struggling to update my IPhone 7 software

loyisopono ~

If your iPhone, iPad or iPod touch won’t update

Updating iOS: common issues and solutions - Apple Community

...found by searching Apple's Knowledge Base.

Also, does your iPhone 7 still have its original battery?

And what's the Maximum Capacity % here?...

Settings > Battery > Battery Health

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loyisopono ~ And, again, what's the Maximum Capacity % here?...

Settings > Battery > Battery Health

To be clearer, this icon is the Settings app:

...Tap it to open Settings app. Then scroll down to Battery and tap it. Then tap Battery Health and tell us what the Maximum Capacity % is. If its value is only "––", let us know that.

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