ROS is installed with gazebo, check the version by gazebo –version, which gzserver, which gzclient to see more info.

Next, we need to install the necessary packages
sudo apt-get install ros-noetic-gazebo-ros-pkgs
sudo apt-get install ros-noetic-gazebo-msgs
sudo apt-get install ros-noetic-gazebo-plugins
sudo apt-get install ros-noetic-gazebo-ros-control
sudo apt-get install ros-noetic-teleop-twist-keyboard

ros-noetic-gazebo-ros-pkgs – is a set of ROS packages that provide the necessary interfaces to
simulate a robot in the Gazebo 3D rigid body simulator for robots. It integrates with ROS using ROS
messages, services and dynamic reconfigure.
ros-noetic-gazebo-msgs – Messages and service data structures for interfacing ROS and Gazebo
ros-noetic-gazebo-plugins – Robot-independent Gazebo plugins for sensors, motors and dynamic
reconfigurable components.
Ros-noetic-gazebo-ros-control – controllers to communicate between between ROS and Gazebo
ros-noetic-teleop-twist-keyboard -package for controlling the robot by using keyboard keys

Then we need to create the workspace and CATKIN package

mkdir -p ~/my_workspace/src
cd ~/my_workspace
catkin_make
source ~/my_workspace/devel/setup.bash
echo $ROS_PACKAGE_PATH
cd ~/my_workspace/src
create the package:
catkin_create_pkg robot_model_pkg gazebo_msgs gazebo_plugins gazebo_ros
gazebo_ros_control

Dependencies are: gazebo_msgs, gazebo_plugins, gazebo_ros, gazebo_ros_control.

STEP 3: CREATE THE SOURCE FILES DEFINING THE ROBOT GEOMETRY
cd ~/my_workspace/src/robot_model_pkg
mkdir urdf
cd ~/my_workspace/src/robot_model_pkg/urdf
gedit robot.xacro
Check the URDF file:
check_urdf <(xacro robot.xacro), edit the file, then create another file

gedit robot.gazebo
edit the file
cd ~/my_workspace
catkin_make

STEP 4: CREATE THE LAUNCH FILE AND LAUNCH THE FILE IN GAZEBO
cd ~/robot_four/src/robot_model_pkg
mkdir launch
cd ~/robot_four/src/robot_model_pkg/launch
gedit robot_xacro.launch
Edit the file and save

Then, open a new terminal and start
roscore
and then,
Finally, we can launch our model in gazebo as: roslaunch robot_model_pkg robot_xacro.launch

STEP 5: Control the robot by Using Teleop
Create a teleop node for controlling the robot. Open a new terminal and type
rosrun teleop_twist_keyboard teleop_twist_keyboard.py
Then, investigate the topics that are being used and published to. Open a new terminal and type
rostopic list
rostopic echo /odom
rostopic info /cmd_vel