I'll be a lawyer. I can help poor people, so I always study hard and  read many books always.  --> I want to be a lawyer. I can help poor people. So I always study hard and read lots of books.  

I want to be an astronaut. I want to go to moon. I'll meet some aliens either.  ✔​

I like looking the mirror. I want to be an famous actress. If so I can see much more actors and actress. -->I like to look at the mirror. I want to be a famous movie star. I can see many entertainers. 

=> Another way: Your sentences are okay and these are another way of saying it.

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