At work

I work at [or "in"] the Legislative Branch in the Rio Grande do Norte state government*, Brasil. I developed my tasks in the Operation and Maintance departament. It is not my dream job, but there it is from there that I earn my income (a very idiomatic way of saying this is: "It's not my dream job but it pays the bills!"). I've been studying to become a biologist and I want to specialize in ecology and environmental sciences. It is a hard routine to work and to study and I usually get exhausted. Before my current job, I worked at the Federal Institute of Science and Technology as an administrative assistant. I'm used to arrive at 8 o'clock and leave at 15 o'clock**.

That's all for now, folks. I have to go back to work.

*i think there are two ways I could correct this:

(1) If you want to emphasise where you are: "...in the legislative branch, in the state of Rio Grande do Norte, Brasil" or

(2) if you want to emphasise that who employs you "...in the legislative branch of the Rio Grande do Norte state government in Brasil".

Number 2 seems most likely

** EITHER "I used to arrive.... and leave..." or "I arrived .... and left..." but you can't mix the two