>

Well, that's just simple, isn't it?
Say you have the craving for an omelette. You can't really account for why this is the case; you don't choose your desires. But here we are. Now, not only do you want an omelette, you also decide to go and make one. Again, a decision handed to you via unconscious processes you can't really claim any meaningful control over. So there you are, making an omelette. And when finished, there you are, enjoying an omelette. That is agency; an end is achieved via your actions. 
Surely you're not suggesting that without free will, we'd grind to a complete halt.
The person mugging you has no choice, the you being in pain has no choice but to suffer and worry. If you have no free will then you have no choice over whether you worry or not. >

No, you can't know that the me being robbed feel suffer and worry. It's also possible that I won't care, because I know I can't choose to feel bad. It is, as it has been mentioned, already determined, what I will feel. >


you are not responsible for procrastination, for being lazy, for not contributing to society, being unkind, and everything else. Its not in your control anyways. Since there is a good chance that free will doesn't exist, should we really worry about anything?  

Well, you're in a society where your actions have effects and create reactions, whatever you are responsible for it or not. Steal, and you'll be jailed, whatever you did it because you are evil or because you were socially predestined to crime. Eat 2kg of meat each day and you may get a heart attack, whatever you are responsible for such a choice or not. 
Some outcomes (being rich, being happy, having a beautiful & intelligent partner) are better than other (being sick, being lonely, living under a bridge) so of course you should worry about what you do, even if ultimately, you were predestined into worrying about them and therefore obtaining what you get. >

A lack of a belief in free will does not necessitate adherence to fatalism. Even non-believers of free will acknowledge that you can’t make an omelette without breaking some eggs. In the same way one can acknowledge that even if ultimately our motivations are simply handed to us via unconscious processes and aren’t “free” in any meaningful sense of the word, it is still sensible to apply our agency in ways that lead to better outcomes.
Fatalism and lack of belief in free will absolutely do not need to go hand in hand.
Edit: Typos and shit, I blame my mobile phone. >

i don't get it, if we don't have free will how do we "apply our agency"?