my youngest son has an iphone and I have an android.

What exactly do you want to set up?

Do you have any Apple device, iPad, Mac, iPod touch?

If you don't have an Apple device, then there's no point and no way to create a Family Sharing group directly.

If you are trying to set up Restrictions, you can do so directly from his iPhone, in Settings ➜ Screen Time.

Otherwise, explain exactly what you want to set up about the iPhone.

To learn how to set up Family Sharing, read this support article --> Set up Family Sharing - Apple Support

- Only lists doing this on an iPhone, iPad, iPod touch and Mac.

To do any kind of management requires Apple hardware.