You will need a For Loop that will loop through rows.
Something like this (Code is untested)
Assuming Cells(Counter, "J") generates the link
Sub extract()
Dim IE As InternetExplorer, Counter As Integer
Dim html As HTMLDocument
Set IE = New InternetExplorerMedium
For Counter = 2 To Cells(Rows.Count, "J").End(xlUp).Row
IE.Visible = False
'IE.Navigate2 "https://company1.com/Person.aspx?accountname=AMERICA\Bob.Joe"
IE.Navigate (Cells(Counter, "J"))
' Wait while IE loading
Do While IE.Busy
Application.Wait DateAdd("s", 5, Now)
Loop
Set html = IE.Document
Set holdingsClass = html.getElementsByClassName("scalerClass")
Cells(Counter, "H").Value = holdingsClass(0).textContent
Next Counter
'Cleanup
IE.Quit
Set IE = Nothing
End Sub
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