You will need an account, go to https://firebase.google.com/ get everything setup.
Install the Firebase CLI tool:
npm i -g firebase-tools
In your browser go to your firebase console
In your Terminal, log into your firebase account
firebase login
Initialize your project
firebase init
Use the arrows to highlight 'Hosting: Configure and deploy Firebase Hosting sites' use the space select this option and then enter to confirm.
Compile your code:
yarn build
then
firebase use --add
select the targeted project, add an alias (referenced in the .firebaserc file at the root of your project, you can just use 'default') for the deployment, then
firebase deploy
Your application will be accessible now at the domain 
Add your firebase token to GitHub Secrets as 'FIREBASE_TOKEN'; to get this run:
firebase login:ci
At the root of your project add '.github/workflows/main.yml'
name: Firebase Deployment
on:
  push:
    branches:
      - master
jobs:
  build:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v1
    - name: Build
      run: |
        npm install
        npm run build
    - name: Firebase Deploy
      run: |
        sudo npm install -g firebase-tools
        firebase deploy --token ${{ secrets.FIREBASE_TOKEN }} -P your-firebase-project-name
Now every change to the master branch will compile and push your code to firebase.