I just joined an affiliate program that allows you to use an affiliate link guard by using a php or html file to hide your affiliate ID. I have no idea how any of this works. I downloaded a file in both php and html form but have no idea how to use them!
These were the instructions I was given:

I’m assuming that this is why I am getting a broken image and no hyperlink from the affiliate provided banner? (see pic below)

or is there something wrong with the code?

Please tell me how I can do this! Thanks!