how can I install package to wwwroot in mvc core 2???????????!!!!!

Recently I Installed the VS 2017 Which Contains Asp.net mvc core 2

but there is a very confusion problems here!

that is how can i Install a  new package into the wwwroot so:

_ Im using bower but supporting is end of and can not find out bower.json in the project>> new item after config it using npm . I installed it using npm but still can not find( .bowerrc file under bower.json.) to set the directory:

So-called valid document

_with gulp and grunt : end of supporting gulp too and can not find gulpfile.js in the project>>new Item after configure it using npm

please heeeeeeeeeeeeeeeelp me