Live exchange currency VBA code

Good evening all
im looking for code that can be used in excel to live update of currency

i found code online but its still give me error
first they need access key and i register with site and now have access key but not understand how can add to code
second
its give error in the following line
response= "1 " &a& "=" & replace(exRate,:""":","") &""&b


i appreciate your support and help

dear Alphafrog
thank you so much for your replying and concern
the problem it will not available with office 2019 that why looking for another solution