I am fed up

Why am I fed up? With (While common is speech, it is considered poor english to begin a sentence with a preposition) people controlling my life and telling me what I must do every time.
I am an adult, I know what to do in my personal life. I have the impression that my mother wants I do what she wants I do and thats irritating. I'm not sure what you are trying to say here. My best guess is: "I think my mother wants me to do what she wants and that's irritating"
It's ("It's" is a contraction of it + is, "Its" is a possesive pronoun) time to take the control of my life.

I am fed up

Why am I fed up? The people cotrolling my life and telling me what I must do every time.
I am an adult, I know what to do with my life. I have the impresion that my mother wants me to do what she wants me to do and thats irritating.
Its time to take the control of my life.

I am fed up

Why am I fed up? With people cotrolling my life and telling me what I must do every time.

First sentence is a fragement the way it is and they way it has been corrected.  Better to repeat the question, "I am fed up with people controlling my life.... " Or rephrase: "People are controlling my life and telling me ...."

I am an adult, I know what to do in my personal life. I have the impresion that my mother wants I do what she wants I do and thats irritating.
Its time to take the control of my life.