How to pass multiple parameters from Angular form to make POST request? [closed]

According to your question, if my understanding is correct, You want to pass parameters while making post request.

You can do something like this:

const val = this.form.value;

 this.http.post('url', {
      first_name: val.first_name,
      last_name: val.last_name,
      email: val.email,
    })
      .subscribe(response => {

      });

You should use the HttpParams library to add multiple params in your request headers.

import { HttpClient, HttpParams } from '@angular/common/http';

onSubmit(values val){
  let params = new HttpParams()
      .set('username', val.username)
      .set('password', val.password)

  this.http.post("A URL", params).subscribe();

}