Unable to accept iCloud Terms and Conditions on iPhone

Settings in iPhone lead me to the Terms and Conditions page, but once I click Continue, it turns gray and the pinwheel never stops turning.

My iPhone is an older model (7plus), which may be Apple’s way of forcing me to upgrade because the last allowed update is 15.8.3. If I upgrade phones without iCloud, moving my stuff to a new phone will be a disaster. Anyone have a suggestion?

[Re-Titled by Moderator]