This is the 409th most frequent Dutch word.
doe
"Do" or "perform."
Here, 'doe' is the conjugation of the verb 'doen' (to do) for the first person singular present tense, 'ik' (I).
Ik doe mijn werk met plezier.
I do my work with pleasure.
In this sentence, 'doe' is used as a form of an imperative, asking someone to perform the action indicated.
Doe het raam alsjeblieft dicht.
Please close the window.
In this question, 'doe' is again a conjugation of 'doen' (to do), applied for the second person singular present tense as 'je' (you).