Hi,
I have some supplementary learning that require student to download and kept for reference reading. How to I create a link on the course and point it to the download server?

Thank you for your advice!

If the supplementary stuff your offering might change then obviously a fixed link isn't going to be very helpful.
I'd probably go simple and just have an iframe that opens the relevant folder on the server and that will display the files. Should be a click to open and or save to the local PC.

If this supplementary stuff doesn't change often bundle the files into the module itself and open with a link to the document itself.