Sub FindHashAndStyleNext()
' Paul Beverley - Version 19.01.23
' Finds a hash and changes the style of the following paragraph

myStyle = "Heading 1"

Set rng = ActiveDocument.Content
With rng.Find
  .ClearFormatting
  .Replacement.ClearFormatting
  .Text = "#"
  .Wrap = wdFindStop
  .Replacement.Text = ""
  .Forward = True
  .MatchWildcards = False
  .MatchWholeWord = False
  .Execute
End With

myCount = 0
Do While rng.Find.Found = True
  myCount = myCount + 1
  rng.Expand wdParagraph
  rng.Collapse wdCollapseEnd
  rng.Expand wdParagraph
  If myCount Mod 20 = 0 Then rng.Select
  rng.Style = myStyle
  rng.Collapse wdCollapseEnd
  rng.Find.Execute
  DoEvents
Loop
MsgBox "Changed: " & myCount
End Sub