cable on SE
The cable I received with the phone doesn't have the USB connector end...rather, two small connectors. Can I use the one I had for my iPhone 6?
iPhone SE
Hello,
Yes, the charger and cable from the iPhone 6 will work just fine.
To use the cable that came with your new phone, you would need an adapter similar to this one:
20W USB-C Power Adapter - iPhone Accessories
This second option will give you the added benefit of fast-charging:
Good luck.