Here's my same Github comment about this issue
For some reason terminal which runs catkin_make haven't sourced ros setup file.
Workaround for _bash: catkin_make: command not found_
- In Roboware Studio open any ROS workspace.
- At the top left corner to the right of drop down menu |Debug \/| click a gear icon. It will open tasks.json file.
- In tasks.json file find "catkin_make". For debug configuration it will look like:
"catkin_make -C ${workspaceRoot} -DCMAKE_BUILD_TYPE=Debug"
- Prefix catkin_make with 'source <ros_installation_setup.bash_path>; ' and save the file. For me it looks like (note that I use ros melodic and it's installed in /opt directory):
"source /opt/ros/melodic/setup.bash; catkin_make -C ${workspaceRoot} -DCMAKE_BUILD_TYPE=Debug"
- Repeat 3rd and 4th steps for other build configurations you want (Release, Debug (isolated), etc.).
- Press build icon and it should work.