To use Ubuntu for 3D modeling and animation, you can do the following:

1. Install Ubuntu on your machine. You can do this by creating a bootable USB drive and using it to boot the machine, or by using virtualization software like VirtualBox.

2. Once Ubuntu is installed, log in and update the system by running the following command in the terminal:

sudo apt update && sudo apt upgrade

3. Install any additional software you may need for 3D modeling and animation, such as Blender, Maya, or Houdini. You can install them by running the following command in the terminal:

sudo apt install blender maya houdini

4. To install additional plugins, scripts and addons you can look up their documentation, or check the software’s website for instructions.

5. To use the software you installed in step 3, open it by searching for it in the applications menu or by running the command in the terminal.

6. To improve the performance of 3D modeling and animation software, you may want to install and configure a graphics card driver.

7. Start modeling and animating by following the instructions provided by the software.

8. Keep your system updated and always check for security patches and updates.

It’s good idea to have some knowledge of 3D modeling and animation concepts, as well as some experience using the software you choose before starting with a project.