Can I charge a DC 5V - 2.15 A power bank with an Apple Macbook charger? Can I charge the following power bank with a macbook chager?

Power bank input: DC 5V - 2.15 A  (Input port: Micro USB)

Macbook charger: Apple 29W USB-C Power Adapter: 5.2V @ 2.4A, 14.5V @ 2A

(with USB > Micro USB cable)

thanks
Yes, that is entirely possible. The power bank accepts standard USB power, and the MacBook charger with USB-C will be just that when you add the USB-C to micro-USB cable.

Note ofcourse that it won't charge faster than the standard charger. Even though the MacBook charger is a 29W charger, it won't charge your power bank at the full rate (instead it will charge at somewhere between 2.6W and 7.8W - most probably at 4.68W).