如何以Angular 改变环境

In my project I have 3 environment files (dev, staging, production). And I want to change the them for each dist folder (when deploying to dev I need the envi dev link to take the data from.. same for staging and prod) The files contains these

export const environment = {
  production: true,
  hmr: false,
  backend: false,
  staging: false,
  apiKey: 'prodKey',
  API_URL: "my backend link"
};

Of course the production is false in dev and staging envs.. I also added in angular.json this (same for staging)

"configurations": {
            "production": {
              "fileReplacements": [
                {
                  "replace": "src/environments/environment.ts",
                  "with": "src/environments/environment.prod.ts"
                }
              ],
              "optimization": true,
              "outputHashing": "all",
              "sourceMap": false,
              "namedChunks": false,
              "extractLicenses": true,
              "vendorChunk": false,
              "buildOptimizer": true,
              "budgets": [
                {
                  "type": "initial",
                  "maximumWarning": "2mb",
                  "maximumError": "5mb"
                },
                {
                  "type": "anyComponentStyle",
                  "maximumWarning": "6kb",
                  "maximumError": "10kb"
                }
              ],
              "outputPath": "dist/production"
            },

But when I do build I usually commment a file and use the other to do build and deploy as here in my api file

import { environment } from 'src/environments/environment';

// import { environment } from "src//environments/environment.stage";
// import { environment } from "src//environments/environment.prod";

const API_URL = environment.API_URL;

commmands are: ng build and ng build --configuration=staging and ng build --prod

But I dont want to keep commenting the API envir.. as above, I want it to change automatically after I do build and change in dist files for each environment so I can deploy normally to git and do normal pipeline.

Any idea? Thanks