iPhone update, help.

Hi there, there is a free app called magic cleaner. This will free up some space.
If you store a lot of photos then download shoebox another free app. This will automatically store all photos and you can retreive them as you need from any device.
Clear all emails and any unwanted music, delete apps you do not use v
Delete old texts and what’s app chats v

Sorry, haven't the foggiest. Is there someone near you who sells used phones? If so, go in and look helplessly at the young lad about the same age as your grandson standing behind the counter and get him to solve the problem.

I spent my late teens and early twenties playing little and helpless, and now play old and helpless. It works every time.