Which is the particle system where i can change the particle type to a alpha image?
Also unlike the image, i need to make it like the particles falls from the center of the image, like a dark hole with no end (but a 'simple hole' not one 3D with 'curves')
Or actually more like this, like rect lines falling from the center:
How can i make something like that in simple steps? like, to change the main single particle, then adding it random and then make a particle effect coming from the center in rect lines?
I hope someone can help me how to do this some steps, because when i add a particle system the particles it doesnt look like what i need, i would be really thankful.
The steps depend on the particle system. The top example is best done with 3rd party plug-ins like Text Anarchy or Particular. The particle systems included with AE are fairly limited. You control the look by adjusting the physics parameters. You could just poke around in the effect and see what each control does but it would be more efficient to pick your particle system, Adobe - Search: cc particle systems ii for example and just type that in the Search Help field at the top right corner of AE and go through some of the training materials that show up. You have asked too many questions to get a single answer to them all in one post.
One other thing to consider. Particle systems generate particles. If you want something to look like it is disintegrating or falling apart then you have to start with the image assembled then use the pieces as particles and make them move. If this were my project and I didn't have any 3rd party plug-ins I would probably start with shatter and a custom shatter map and a comp camera to get the angle of view that I wanted.