In above "submodules_structure" , we added 3 repos.
The keys---"paLibSubs","paLibSubs/paMods/display"---represent the relative path to "root_folder" that your submodules will be in.
"used" represents if you need to load it
"git" represents your submodule repo
"rename" represents the folder name of your submodule you want to change to. This part is not necessary to write, if you don't write it, it will be load as it's own name in URI.
Run update command
ctrl +shift+p and type subhelper,then type enter
It will automatically run and load your submodules.