Hola,
I have only 1 action attached to all enemies and i set their skill1 to their health. Now i want to display their health in a panel over their heads. Is this possible?

I saw in old AUM32 that shows how to display a panel over an entity but it uses predefined global variable, In my case i want to show each entity's skill1.

afaik there is no way to show a local var directly.

but you can use a workaround by displaying a global var and creating a while loop to set its value to the local var you want to show.

But you may have seen it in some games, they show each enemy's health over their head, you mean that is not possible with 3dgs?

I can't use global + local technique because i am using only 1 action for all enemies. so for example using var display_my_health = my.skill1 and displaying it in panel will not work because all the entities are using the same action.

it is possible as long as your function is "alive"
just create your panel with pan_create and add objects to it with the pan_set* functions
but don't forget to delete the panel before exiting the function

You can also use draw_obj to do so. The example code in the manual should be a good starting point - if you decide to use a TEXT like in that example, just set the string using the str-instructions to something that shows their health (a simple str_for_num(NULL,my.skill1); would be enough here). If you so desire, you can also color the text by adjusting the settings beforehand.

If that sounds like too much work, you can also always use draw_text.