you need to be more specific. I don't know what new Super Mario game you're talking about. Is it New Super Mario Bros Wii or New Super Mario Bros (DS)? And what level? is it 2-A (DS Mario game) or another level? If you answer all these questions in your question, I can figure out what you need.
For New Super Mario Bros., You reach level 7 by defeating the level 5 final boss (Petey Piranha as mini Mario
how do you pass world 6 on level 6 on new super Mario bros
Beat the boss at the end castle on level five as mini Mario.
You can't.
You beat level 1.
no in new super Mario bros there is no level 0 there is only worlds like world 1,2,3,4,5,6,7,8
Blue mushrooms in New Super Mario Bros. make you small.
beet world 5 boss as mini Mario
Just beat 5th boss as Mini Mario.
You can't. It is impossible
On the last level of world 2 use tiny Mario to fight the monster and you can get to world 4 with tiny Mario
You have to beat Mummipokey (the boss of World 2) as mini Mario.