high speed bullet trains leave from Guangzhou for Beijing and from Beijing back please

Can you please tell me when the bullet trains leave Guangzhou to Beijing and when do they leave Beijing to Guangzhou both on weekdays and on weekends and what are the prices for the most comfortable accomodations for the trip please for 3 people? Are there any other fees involved and are there dining cars or should we bring food with us ? Any other information would be greatly appreciated. Thanks!!! Is there a website where I can book these train tickets in advance please?