I need IOS 15.6 update please

If your details are correct and you are running iOS 13, then yes.. updating to iOS 15 would allow you to use Google Photos as it shows a requirement of iOS 14 or later

Update your iPhone, iPad, or iPod touch - Apple Support

because you are years behind with your updates, you may need a computer to update

need more storage for update?

If you need more space for an update on your iPhone, iPad, or iPod touch - Apple Support

issues?

Updating iOS: common issues and solutions - Apple Community

video..

I need iOS 15.6 update for my 7 Plus

so update it then.. links are provided in this thread

I want to update iOS

Read the rest of the posts in the thread you added your post to.