I purchased the top-tier bundle that includes beta access, but the game isn’t available for download in the Battle.net client—it simply isn’t there. macOS.
Firstly, ew. Using a Mac for gaming? What the hell? 
Jokes aside, try searching for how to force the WoW Forever installation on Mac. There were people posting links with commands you can enter that should force Battle.net to start the download.
I also wouldn’t bother mentioning that you bought the top-tier bundle. Just say you bought a bundle that includes beta access. You’re not going to get special treatment because of which bundle you purchased.
Try the forum search as well, because I think someone posted the command in one of the threads. Hopefully you can find it and force the Battle.net launcher to install the client.
its dosnt work
Have you gone here and tried this?
Also there is this thread on the US forums, which has some information: