Question

how Nazi party destroy other political parties

Answer 1

after coming in power Hitler sidelined the Parliament and Rule By decree. All trade unions and other political parties were declared illegal other than the Nazi party.
Hitlee delivered very powerful speech and covinced the civilians of Germany fo everything and the Nazi party become a autocratic party.

Answer 2

the hitler use his brilliant brain and germany want the dictator to help them so hitler take advantage of it and defeat all the parties of germany and made the dictator of germany.