Hi. I'm trying to install ros.

First of all, I'm on ubuntu 20.04

I tried to install ros melodic, kinetic and finally noetic but the latest was the only one found by my apt-get command. I then installed noetic using aptitude because apt-get had an unsolvable issue of unmeet dependencies.

No I'm trying to run catkin make on git cloned rosjects, bu i encounter the error bellow:

CMake Error at /opt/ros/noetic/share/catkin/cmake/catkinConfig.cmake:83 (find_package):
Could not find a package configuration file provided by "rospy" with any of
the following names:

rospyConfig.cmake
rospy-config.cmake

Add the installation prefix of "rospy" to CMAKE_PREFIX_PATH or set
"rospy_DIR" to a directory containing one of the above files.  If "rospy"
provides a separate development package or SDK, be sure it has been
installed.
Call Stack (most recent call first):
openai_ros/openai_ros/CMakeLists.txt:10 (find_package)

I solved it by doing sudo apt-get install ros-noetic-rospy but then I got:

Command 'rosdep' not found, but can be installed with:

sudo apt install python3-rosdep2

So I did the said command "sudo apt install python3-rosdep2", but now I got the first error again (the one about rospy) so I iterated a bit more in this poop loop, by trying to install these packages in another way (I tried sudo apt-get -y install python3-rospy) but I still got this error. How can I solve it ?