1.How many years did HITLER rule Germany?

 

2.How was Hitler able to differenciate between geman people and jewish people?

Hitler ruled Germany for 12 years. He became the Chancellor of Germany in 1933. In the same year, with the passing of the famous Enabling Act, Germany became a dictatorial state and Hitler acquired all the powers. He continued to rule Germany till he committed suicide in 1945.

Please ask second query as a separate question.