Although Apple’s representatives don’t comment on incidents under investigation (and they shouldn’t), the company has issued a security update after learning that a human rights activist’s phone data was compromised.
Links to the USA Today report and Apple web page where you can find information on the iOS 9.3.5 update appear below. The update is compatible with some other devices besides the iPhone, and those devices are listed on Apple’s page.
I bought my iPhone earlier this month, and am still learning how to use it. However, the instructions for installing the update are simple and I had no trouble. If you have difficulty — or you just lack self-confidence — do not be discouraged. Get a shower, go for a short walk, drink a cup of coffee, or do whatever it is you do to clear the cobwebs from your head. Then take another look at the instructions.