VBA Excel Run time error 438 / getElementbyClassName - html

Question

I'm a newbie, attempting to web scrape aspect ratio details from the imdb.com website.
I've plundered some code on You Tube and adapted it using inspect element.
The code opens imdb and runs a search by title but returns a Run Time error 438.
Ideally I'd like it to return the html of the top result so I could perform a further click the top result to follow through to the page with tech details from where I could get the aspect ratio information and paste it into a cell.
Unfortunately I get a fail from my Click instruction - haven't even got to the point of extracting the aspect ratio info.
Can anyone see where I've gone wrong?
Many thanks,
Nick
Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Row = Range("Title").Row And Target.Column = Range("Title").Column Then
Dim ie As New InternetExplorer
ie.Visible = True
ie.navigate "https://www.imdb.com/find?ref_=nv_sr_fn&q=" & Range("Title").Value
Do
DoEvents
Loop Until ie.readyState = READYSTATE_COMPLETE
Dim doc As HTMLDocument
Set doc = ie.document
Dim sDD As String
doc.getElementsByTagName("a").Click
End If
End Sub

Answer 1

So, addressing your code
You can use a shorter version of Target.Address = Range("Title").Address
You don't want the first a tag element. You want the first search result a tag element.
You can use a CSS selector combination to get the first search result a tag element as shown below.
I use a CSS selector combination of .result_text a to target elements within parent class result_text with tag a. The . is a class selector.
This combination is known as a descendant selector.
Using search term in sheet of Red October this is what the CSS query first result is:
It is a relative link with base string https://www.imdb.com.
Applying via querySelector method means only first matched result is returned i.e. the top result.
VBA:
Option Explicit
Private Sub Worksheet_Change(ByVal Target As Range)
Application.EnableEvents = False
If Target.Address = Range("Title").Address Then
Dim ie As New InternetExplorer
ie.Visible = True
ie.navigate "https://www.imdb.com/find?ref_=nv_sr_fn&q=" & Range("Title").value
Do
DoEvents
Loop Until ie.readyState = READYSTATE_COMPLETE
Dim doc As HTMLDocument
Set doc = ie.document
doc.querySelector(".result_text a").Click
'other code
End If
Application.EnableEvents = True
End Sub

Answer 2

This line of code:
doc.getElementsByTagName("a")
gives you the Collection of Hyperlinks in your HTML Document. That is, it gives you ALL the elements that match your given criteria, if any are available.
However, some issues may arrive:
There may not be any hyperlinks available - So there are no elements to click on.
You are not referencing any element to click. If you want the first one in the collection of found items, you could go with the index, as suggested. Else, you might look for another clicking criteria (such as what is its text or another given attribute).
Even still, a found element might not be clickable by your browser, if, for example, it is shadowed by another element.