iPhone XR will not connect to any Wi-Fi network

CK ~ 84% is not great, but may be ok. (Apple regards 80% as borderline unhealthy.) See if this helps:

If your iPhone, iPad, or iPod touch won't connect to a Wi-Fi network

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

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CK ~ 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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CK ~ Does your iPhone XR still have its original battery?

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

Settings > Battery > Battery Health

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