"I will get off at the next station."
First, you need a particle after 次の駅. It should be 次の駅 で．Second, why use 私は? It's implied that you are the one doing it, you don't need it at all and in fact it is extraneous to use in Japanese. In english you need the "I" in "I am getting off at the next station". You don't need it in Japanese. So, that part is actually incorrect.