I scratch a bump that looks like pimple on my nose a white small solid subtance came out. and the hole is quite big where the substance came off. y??

Clogged pore: the white stuff that comes out is cebum or debris within a pore or small sebacious cyst. It is best to NOT saqueeze, but to regularly utilize a good skin cleansing routine.

Just a pimple: The plug of sebum can be big enough to stretch the pore. A couple of warm showers will help it get back to normal. Try very hard not to scratch. Can get infected.