It says something about my storage and won’t let me do it how do I do that

That means you need to free up some space before you can do the update. Some ways to free up space:

1. Turn on iCloud Photos from settings: Go to settings, your name at the top, click on iCloud and turn on iCloud Photos.
2. Turn on iCloud Drive. Go to settings, your name at the top, click on iCloud, then turn on iCloud Drive.
3. Delete any apps that you don't need.
4. Go through your photos and videos and delete some that aren't important to you.

Another way to free up a lot of space quickly is to transfer all your photos to a Mac or PC, then transfer them to an external HD, then you can delete them all if you want. Transfer photos and videos from your iPhone or iPad to your Mac or PC - Apple Support

Please see this article: How to check the storage on your iPhone and iPad - Apple Support

Hello ~ Any help here by clicking on below?

Manage your photo and video storage - Apple Support

What's the difference between device storage and iCloud storage? - Apple Support

Post back if needed and take care.

~Katana-San~