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.

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

Check all your folders, do a spotlight search.

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