I create objects every seconds with code and they have random position but someone's body_entered works, someone's does not work. How can i fix it ?

We need more information to help you.

Can you upload a .zip containing a minimal project that illustrates the problem?

    The problem is that you are checking for the name "Sushi", but only some of them have that name. See the attached image.

    A better way is to use groups.

    In Area2D.gd, change:

        var object = sushi.instantiate()

    to:

        var object = sushi.instantiate()
        object.add_to_group("sushi")

    In space.gd and stick,gd, change:

        if body.name == "Sushi":

    to:

        if body.is_in_group("sushi"):

    Thank you for everything. it works and most important thing is that i understand where is my wrong.

    You're welcome.

    Also, the way that you are generating sushi's is strange. Instead of using a recursive function call (createSushi calls itself), it would be clearer to add a Timer that runs every two seconds and whose timeout signal creates a sushi.