hi, how could i make some graves with animated worms or another stuff from the game?

i assume i must capture the animated object and then export it to a gif or something like that.

help pls

It's not possible to make custom animated graves.
All you can do is use 3rd party team editors and use one of the sprites that are used by the game itself.

This is disapproved by most players though, as those game sprites are big, flashy and annoying most of the time and also tend to cover parts of the landscape.
Don't do it. Stick with default or none-animated ones.