U should physically present at campus for first round of councelling for which they will mail u the date n time. Then u should pay 11k to them in which 10k will be returned back after councelling.
U should fill ur branch preferences there. Don’t worry if u won’t get branch of ur wish in first round, u will get it in further rounds for which results u can see in online and u can opt out in any round .
Don’t worry about accommodation as they will provide hostel rooms to stay for 2 days n it costs lesser than most of the hotels.
All the best.