Thank you very much for your time and help. This is also a way to do it.
Nevertheless I couldn't fix it the way I wanted. In previous projects with Limb IK I could just move the puppet down and it would bend the knees. This time, it gets stuck to the background. I applied the Limb IK to the front puppet. I wonder if there's a way to fix it. If somebody knows.. I'd appreciate it. I leave the rigging I did...
no, the problem of the puppet is that I cannot make him sit, or kneel... because everytime I try to do that the neck is stuck with the background... like there was a pin or something fixing it with the background...
IN the following picture, I show you an earlier project, and I can use Limb IK and make it kneel....