How can I list all available software environments?
module avail or module av
How can I list my software environments?
module list or module li
How can I list a specific software environments?
module avail matlab or module av matlab
module avail intel or module av intel
How can I get deeper information of a specific software environment?
module whatis matlab/v2021b
module show intel/v2019
module display comsol/v60

How can I set (load) a specific software environments?
module load matlab/v2020b
module load intel/v2020
Hint: Please check with module av matlab for an existing environment!

How can I unset (unload) a specific software environments?
module unload matlab/v2020b
module unload intel/v2020
Hint: Please check with module av matlab for an existing environment!

How can I unload all (!) software environments in the current terminal
module purge

It is recommended to load only the necessary software environments in an interactive terminal and in a batch job:
module purge; module load ansys/v2022r1
module purge; module load comsol/v60 matlab/v2020b

How can I get more help to the module command?
module help
man module