Where is Clipboard on iPhone

There is no such in an iPhone.

You will have Clipboard only when it can store multiple Cmd C or X, In an iPhone, you can store only one i.e. the last cmd X or C.

If you have used cmd C, then you can use cmd V anywhere (Notes, Message, Search field etc)

Just tap on any text field and select “paste”.

You can’t visually see what’s on your clipboard unless you paste it.