How do I set up a family sharing Account for my sonIf I don’t have an Apple iPad and he does

It can be done using one device, but it is a bit more difficult using only one device. On the device, sign into iCloud with your Apple ID and set up Family Sharing. Create the child's ID if necessary. Sign out of your ID and sign in with the child's ID. Swap iCloud sign in as required.

Family Sharing.         

Family Sharing - Set up.       

Apple ID - create a new.      

Apple ID – Create        

If the child is less than 13 years old, you will need to set up Family Sharing. It can be done using one device, but it is a bit more difficult using only one device. On the device, sign into iCloud with your Apple ID and set up Family Sharing. Create the child's ID. Sign out of your ID and sign in with the child's ID. Swap iCloud sign in as required.

What if the child is over 13? We only have one Apple device and I can't figure out how to add them to our Family Sharing without them having their own device.