Ensure you have npm installed, if you don’t please read the blog Easy steps to installing Node, NPM, TypeScript, and Bower in Windows
Once installed execute the following:
npm install –g @angular/cli
To verify you have access to ng launch a command prompt and type in
ng --version
If you receive a message that it is not recognized as an internal or external command, update your PATH environment variable to include the following:
%appdata%\npm
Try ng --version again to see if it displays the version information. Once working create your project:
ng new your-project-name
Per guidance provided by the official Bootstrap site (excerpt below) install Jquery, Popper.js, and Bootstrap.

With npm installed (above) execute the following:
- npm install bootstrap
- npm install jquery
- npm install popper.js
Update the src/styles.css with the following:
@import "~bootstrap/dist/css/bootstrap.css";
Update the angular.json scripts section with the following:
"scripts":[
"node_modules/jquery/dist/jquery.min.js",
"node_modules/popper.js/dist/popper.min.js",
"node_modules/bootstrap/dist/js/bootstrap.min.js"
]
Note: angular.json has been renamed from angular-cli.json

Now you are ready to use Bootstrap in your Angular application