I found a lot of my leaves with this spots and little black bugs, someone knows what that is and how can I get ride of that?

Those spots are the result of the mining/feeding activity of the larvaes of the bugs, or the bugs themselves.
Insecticides from bio solutions (Neem) to systemic ones are working.

(Edit: What kind of maple is it? A similar seedling growing on one of my pots. Still unidentified, but maybe sycamore maple... I think..)