How can i gain weight extrememly fast?! this is really important!!?

im not giving you my weight and age but i'll tell you somehow i lost 3 pounds and i cant afford to lose anymore weight or its the feeding tube. im serious. feeding tube. so how do i gai nweight really quickly? keep in mind that im only a child and therefore have little resolve and tolerance to work out. does wii fit help? ive been playign the strength exercises recently... so i guess thats my limit for working out, playing wii fit. and dont say protein shakes, those are disgusting. gramma bought me these pediasure shakes or something like that. do these help? they're not exactly tasty but not that bad either...