How do I know if I have the latest update

Go to Settings > General > Software Update.

Update your iPhone, iPad, or iPod touch -

https://support.apple.com/en-us/HT204204

Hi,

• You can check for new iOS updates by opening the settings app > tap general > tap software update. It will either show a new update if available or it will say that iOS is up to date.
• To prevent any issues updating, make sure to download a new update with Wi-Fi and make sure your iPhone has at-least 3gb of free space, you can manage storage in settings > general > iPhone storage.