Adding 3rd party frameworks

Hi all.
I am learnimg Sage. Yesterday I’ve installed Trellis and Bedrock with success.
I am having problems with installing 3rd party modules.
After running ‘yarn add mdbootstrap’ command I have this module as dependency and I see files in ‘node_modules’ folder, but it is not showing in autoload folder and it is not working.
What I am missing here?