Workout help for an already skinny 15 year old?

okay so i have 2 months of summer left and i want to workout all day the rest of the summer . I have a good 4 pack and a 6 pack that shows on a good day . If i just push my fat down you could see the six pack . i never worked out to get this 6 pack though, all i i did for exercise was play basketball everyday(which i still do) . i did workout but just a lil bit . i want to have a better 6 pack one that really shows and i want to get some chest too! id like to know what workout routines i can do everyday so that i could get to the nicer body . id also like to know i diet plan i could take . once again im very skinny , and i eat so much junk food and everything , yet im still skinny . id like to know what do i start eating so that it wont affect my workout . id also like to know what do i buy at walgreens or something . one of those things like muscle milk to make me bigger ? idk much about this workout stuff please help . (i play basketball everyday at a local elementary 2 blocks from my house , i walk to go there and to come back , it has a big feild that i could maybe jog and stuff . i have no weights , no workout stuff at all . im willing to dedicate as many hours as you guys suggest me , please help )