Linking to an external site means you always need to give the full address. This includes the host, any subfolders, as well as the final file that you wish to link to. Additionally, you will need to prepend the protocol. As of 2019, Google and others are recommending everyone be using https (Hyper Text Transfer Protocol Secure), followed by a colon and two forward slashes.
Most websites can handle the secure request, but you need to verify to make sure that it is not using just http.
The sub-domain may not always be present. It depends upon the host that you are connecting through.
The subfolders may or may not be there as well.
If the file is not provided, then the web server will look for a series of default files, and try to display them. The whole filename has to be given, including the correct extension. If the file is missing, misspelled, etc., then it will not be able to find the file and fail.
Creating External Links from your Website was originally found on Access 2 Learn