Angular4 based web application development life cycle

I am a newbie in Angular world, but I am seasoned backend programmer (java and golang). I have few questions.

1.) Does angularjs app need to be served using nodeJS on the server side?

2.) Is angularJS only client side code? if that is the case, can I serve it simply using apache?

3.) If AngularJS is client side code, does it not impose security risk, because it calls API and all the API keys and secrets are embedded in the javascript.

Maybe I am missing something here.

Really appreciate some pointers. I tried to look around the web, couldn't find a satisfying answer.

Thanks, Brijesh

via brijeshchavda