Without seeing either the template or the document content, the following should work to save the documents to PDF in the same folder and with the same names as the original documents.
Code:
Sub BatchToPDF()
'Graham Mayor - https://www.gmayor.com - Last updated - 24 Jan 2021
Dim strFile As String
Dim strPath As String
Dim strName As String
Dim oDoc As Document, oNewDoc As Document
Dim fDialog As FileDialog
Const strTemplate As String = "C:\Path\Letter.dotx" 'The name and path of the template
Set fDialog = Application.FileDialog(msoFileDialogFolderPicker)
With fDialog
.Title = "Select folder and click OK"
.AllowMultiSelect = False
.InitialView = msoFileDialogViewList
If .Show <> -1 Then
MsgBox "Cancelled By User", , "List Folder Contents"
Exit Sub
End If
strPath = fDialog.SelectedItems.Item(1)
If Right(strPath, 1) <> "\" Then strPath = strPath + "\"
End With
strFile = Dir$(strPath & "*.docx")
While strFile <> ""
WordBasic.DisableAutoMacros 1
Set oDoc = Documents.Open(strPath & strFile)
Set oNewDoc = Documents.Add(strTemplate)
oNewDoc.Range.FormattedText = oDoc.Range.FormattedText
strName = Replace(oDoc.FullName, ".docx", ".pdf")
oDoc.Close 0
oNewDoc.ExportAsFixedFormat OutputFileName:=strName, _
ExportFormat:=wdExportFormatPDF, _
OpenAfterExport:=False, _
OptimizeFor:=wdExportOptimizeForPrint, _
Range:=wdExportAllDocument, from:=1, To:=1, _
Item:=wdExportDocumentContent, _
IncludeDocProps:=True, _
KeepIRM:=True, _
CreateBookmarks:=wdExportCreateHeadingBookmarks, _
DocStructureTags:=True, _
BitmapMissingFonts:=True, _
UseISO19005_1:=False
oNewDoc.Close 0
WordBasic.DisableAutoMacros 0
strFile = Dir$()
Wend
lbl_Exit:
Exit Sub
End Sub