Toad levels force you to use the Gamepad and play as Captain Toad. Captain Toad cannot jump but you can spin the camera around and use various features of the Gamepad to complete the level.
Start by walking around and claiming Green Star #1 from the bottom level. Head up the ramp and ride the platform to Green Star #2 then back onto the platform. Move through the left hole to find Green Star #3 then back out through the other hole. Pass by the Biddybuds and up the ramp to the top level, sneaking inbetween the large group of Biddybuds to grab Green Star #4 . Take your time as you move across the thin board to Green Star #5 and the end of this level.