Generally speaking, you don't. Doctor Who is a production of the BBC based out of its studios in Cardiff, Wales. As such, and due to union regulations, you are unlikely to be able to audition for any role in the series unless you are invited or are an actor based in the UK and affiliated with the applicable unions. An exception to this is if the series goes overseas for filming, as it occasionally does. If the series is filming in your area (for example, an episode was shot in New York, another in Utah), it might be possible to sign up to be an extra, etc.
audition what?..
bbc wales
no you dont
Certainly as long as you are legally in the US and you meet the requirements established by the Disney organization, you can audition for them.
You could probably audition, but you would have to travel to where the auditions are being held and then would need to be prepared to move to the US if you were chosen for the part.
In the US, yes, but not in the UK.
It is a closed audition process, so you will need an agent who is well informed about the audition process in the area you live and then can be informed and inform you about upcoming auditions
No all you have to do is speak english and to go to the audition you will have to go to the us or send a video to the walt disney company
yes! only US residents can audition
yes just look around
Be a good singer
Yes