I want to connect a Canon 1500D DSLR with a MacBook Air using wifi in order to transfer files. Is this possible?
Note: from Wikipedia: The Canon EOS 2000D, known as the Rebel T7 in the Americas, as the Kiss X90 in Japan and as the 1500D in southeast Asia.
No, you can't. At least, not according to the How to Send Your Canon EOS Rebel T7/2000D’s Pictures to the Computer article related to the Canon EOS Rebel T7/2000D For Dummies book:
Your Canon EOS Rebel T7/2000D camera’s built-in Wi-Fi system enables you to send photos wirelessly to a smartphone or tablet. Unfortunately, you can’t use Wi-Fi to download files to a computer, even if your computer is connected to a wireless network. Instead, you need to choose one of these options to download your files:
Connect the camera to the computer via a USB cable and use Canon EOS Utility 3 to download files. Canon doesn’t supply the necessary cable, but it can be had for under $15. Canon refers to the cable as the interface cable, which helps to explain the part name: IFC-400PCU. ...
Use a memory-card reader. With a card reader, you pop the memory card out of your camera and into the card reader instead of hooking the camera to the computer. ...