first grow.. need some help

[zcolgan]

my plants are a month old now. i ahve some questions
when is a good time to start giving them plant food? what is the best to feed them?
when and how do i tell if its a female?do you think the fat one could be a male cause of how chunky the leaves are?
i dont know what to do with the whole budding process.. do i leave them alone and let them do their thing? what am i supposed to do to get them to bbud?

THANKS