Can anyone do something intentionally? Consider someone is doing something (for instance eating). I can say that he is eating because of hunger, and his hunger is because his body needs energy. So, every action have external causes only.

Can I do something by my own (without external causes)?

I know that I can't do unwholesome things because of anatta. But I can say that I did something because of ignorance, and also that my action has an effect (karma).

This post may not be a question. I'm looking for a way to clear my understanding.

Kind regards.
Every inside has an outside.  Can you truly say that one has hunger because of only things outside without anything on the inside?  Can a rock be hungry?  Can the vacuum of space be hungry?  There must be something on the inside which is part of hunger, or else it is a thing which is experienced by every part of existence equally.

On the other side, can an action occur without an actor?  If not, and you cannot do something, then no action can occur.

Of course, these are not to say that hunger does not exist, nor that one cannot act.  They merely point out that there are fundamental limits of understanding when one starts from the assumption that things are either completely outside or completely inside.

Phrasings like "I am hungry with my body" and "I act with the world around me" may be worth considering.  They have their flaws too, but they are complementary flaws.