Hi Vartika,
While working with the reinforcement toolbox myself, I found that there was no functionality to create custom Multi Agent environments in MATLAB in the version R2022b. But for newer versions there is a function which can be used to create a custom environment, as the environment mentioned by you is not there in the pre-defined environment. This is the documentation link for the same: https://www.mathworks.com/help/reinforcement-learning/ref/rl.env.rlmultiagentfunctionenv.html
I read in the same documentation that this function has been introduced in the MATLAB 2023b. I suggest you update to a newer version to utilize this.
I hope this helps with your question.
