Can cellular life be simulated with custom built robots?

I want to create a small Amoeba or Paramecium type of creature. Each creature would have sensors for touch all around it’s flexible “cell membrane”, and I’d probably even add vision sensors and other sensors. I saw that Gazebo has SDF for building such custom robots, but I didn’t quite understand how it can be used for creating a custom robot.
What’s also important is that these robots I create should be able to join together and form a larger organism.
Does Gazebo offer such features? 1.Creating tiny custom robots and 2. Robots joining together to form a larger organism?