Hi I need one small help

See;

How to check the storage on your iPhone, iPad, and iPod touch - Apple Support

As suggested above and in the linked articles, that means deleting or offloading some contents.

If you’re well and truly stuck (which can happen), you may have to use a computer to update:

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

See this link --> Clear Other storage on your iPhone or iPad - Apple Support

If you need storage for the new update, try cleaning some unused apps and delete some videos and photos that you do not need.