It is very important to fill out the volunteer form so that you are registered with your email and thus receive the invitation to the next conference call.
No, the most important thing is to want to serve people in dire need in different areas. In the volunteer form you will indicate in which area you want to help.
If you have not yet turned 18, you must participate in the trip with one of your parents or an adult who must send an email certifying that they will be responsible for you.
You just have to ask your doctor if you can travel by plane and have enough medicine for every day since you may not be able to get it in another country.
The accommodation depends on the country. Generally we will stay in a hotel or hostel. You may be sharing a room with another volunteer and all the food will be vegetarian.