How can I print comments at the bottom of the page in Word 2021?

You can print all markup (comments and revisions) at the end of the document, if that helps.

Click File > Print. In the Settings drop down, choose the option "List of Markup":

You can print to a physical printer, or you can print to a PDF converter/virtual printer in order to create a PDF document which would then include the list of markup.

MVP Doug Robbins has created a macro that adds comment numbering. After you have added more comments, you will have to run the macro again for the numbering to update.

For installation instructions, see https://www.gmayor.com/installing_macro.htm. 

Sub NumberComments() 

'Doug Robbins, MVP 

Dim i As Long 

Dim rngComment As Range 

With ActiveDocument 

    For i = 1 To .Comments.Count 

        Set rngComment = .Comments(i).Range 

        With rngComment 

            If Left(.Text, 7) = "Comment" Then 

                .Text = "Comment " & i & " " & Mid(.Text, InStr(.Text, "-")) 

            Else 

                .Text = "Comment " & i & " - " & .Text 

            End If 

        End With 

    Next i 

End With 

End Sub

Good to know we'll have the option not to enable it!

But only temporarily, we're told. If you do enable it and find it as unusable as other users have reported, be sure to send feedback to Microsoft letting them know you don't like it. The least they can do is leave the option to disable it!

Thanks Stefan. I had done that - printing the document and comments separately - but it worked only because the doc was two pages long, with 8 comments. I could easily number the places in the doc that had comments. Won't be practical to do that for long docs.

Do you have Modern Comments enabled? I do not know whether this make a difference, but it may.

I do not know of any way to do what you wish.