go to the 2nd tunnel underground, jump over 2 turtles, collect 40 coins then GROW UP.
if you have unlocked a cannon you will be able to enter a level then when your at the cannon enter it like a pipe
After you use the return pipe you will warp to the level select area just enter one of the doors and it will bring you to the next level
Later on in the game, you gain access to an area known as the pipe yard inside of Bowser. From here you can leave Bowser's body and enter the Mushroom Kingdom. Eventually you will be able to access the castle from toad town after progressing through the story and also the very too pipe in the pipe yard.
you have to hit the ball in the pipe and it appears on the other pipe.
when u start the game take the Fire which can break the block and then in world one level 3 in 1st pipe u will fine there blocks on pipe just breat those pipe n get in. u will be in gomba party.
by eating the squid thingy.
you go down the gold pipe and you get on top of the roof and he is right there
In Super Mario Bros. 3, there are rare items called 'Warp Whistles' that allow you to enter a warp pipe leading to another world.
Mario Raceway
in the pipe room you can .. but it depends where you are in the game. like if you just started then it will be a while. but mainly just go to the pipe room thing. and to get back in , you have to find a pipe with foot prints on it.
Jump on the pipe and press down.
Just walk into it