In VBA for Excel the basic command is
ActiveWorkbook.SaveAs Filename:=Worksheets("Sheet1").Range("A1").Value
A1 would contain the path and filename to save it under, or filename to just
save in default location.
If you want to prevent displaying alerts like "file exists ... overwrite?"
then use this
Application.DisplayAlerts = False
ActiveWorkbook.SaveAs Filename:=Worksheets("Sheet1").Range("A1").Value
Application.DisplayAlerts = True
Just remember that if there are any other errors that take place such as
disk full, invalid path, etc. then things will pretty much just fail rather
dramatically.