I accidentally deleted safari from iPhone. How do I reinstall?

Safari can't be deleted, but it can be turned off in Settings > General > Restrictions

Safari will be at the top of the list. If it's off, turn it on.

Go to Settings > General > Restrictions and make sure the Safari option is set to "on"

Sorry, on iPhone you cannot delete Safari even if you wanted to.

Check all your folders, do a spotlight search.