CType(Page.FindControl Windows equivalent

From Microsoft Documentation:
Searches for controls by their Name property and builds an array of all the controls that match.

'Declaration
Public Function Find ( _
	key As String, _
	searchAllChildren As Boolean _
) As Control()

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Parameters
key
    Type: System.String
    The key to locate in the Control.ControlCollection.

searchAllChildren
    Type: System.Boolean
    true to search all child controls; otherwise, false.

Return Value
    Type: System.Windows.Forms.Control()
    An array of type Control containing the matching controls.

Assuming that you know that there is a Label for each value of i, and that Page is a form:

     Page.Controls("Label" & i.ToString).Text = Label14.Text

If the Label is in the same form as the code then:

     Me.Controls("Label" & i.ToString).Text = Label14.Text