My storage s full how will I do it to get more ,but not deleting

You cannot add storage to your iPhone. All you can do is delete things or buy a phone with a larger capacity.

If you're asking about iCloud Storage (which is for syncing and backing up), see here:

Upgrade to iCloud+ - Apple Support

I’ve got issues with storage I’ve downloaded as much as I can I’ve loads of unsaved apps but it won’t delete them I have no option for deleting them I had way more apps on phone but some haven’t deleted it’s still stored in apps but I can’t access ur delete