A few questions about life as a doctor.

Hello, As long as it hasn't changed in the last couple of years, you usually put in a preference for both. If you want to join a particular medical regiment, such as 16, then it is sensible to put you location preference as somewhere near 16. GDMOs at 16 can ask to do P company (but it's not compulsory), GDMOs in other medical regiments can also ask to do P company. The bursary application is becoming increasingly competitive, but so are the direct entrant applications.

Do you have any advice to increase your chances of selection?

Just take the process step by step (there are lots of steps!), the Army website has information on both briefing and main board. Make sure you are prepared and can easily pass the fitness assessments. Otherwise it is just important to be yourself, they are looking for potential rather than the finished product. It is good to remember they also want you to be a team player.