Hello AppleMember007,
Thank you for using Apple Support Communities.
I understand that when you purchase content from iTunes on your iPhone does not download on your Mac.
For purchase you have already purchased, you can use this support article to download that content on your Mac. You will not be charged for previously purchased content.
Redownload apps, music, movies, TV shows, and books - Apple Support
Going forward, you can use the information in this article to turn on Automatic Downloads, so that when you purchase content on one device, it will automatically be downloaded on your other devices.
Turn on Automatic Downloads or App Updates - Apple Support
Best regards.