I want this update on my phone but I don't have space on my iPhone how do I go about it?

Your profile shows an iPhone 7, but you cannot install iOS 16 on an iPhone 7.

Are you installing iOS 16 on an iPhone 8 or higher?

If there is not enough room for the update, you have to start deleting apps, other data, media, etc to make more room.

How to check the storage on your iPhone and iPadOfficial Apple Support › en-us

You can update to iOS 15.7.2 on an iPhone 7, but that is as far as it can go.