ROM Hack Question on the nsmb editor

[Geno_4_Ever]

I want to delete everything in a level, but dont know how to delete anything. How is it done?

 

[beefymeatloaf420]

I tried the New Super Mario Bros. Editor before. I don't know how much luck you'll have with it, because the GUI isn't very nice and it's kind of frustrating (for me at least). I think to delete you have to do it by one block at a time. :|

 

[Tanks]

I'll make this simple for you kid. You don't. Well actually it's entirely possible, but it requires hex editing and adding in spaces for new blocks to be placed etc etc. In other words, not worth it buddy... :/