firebase emulator commands.txt

nvm install 12.0.0
nvm use 12.0.0
npm install -g firebase-tools
firebase --v
you should be in your project root folder
firebase login
firebase init
only select Functions: configure and deploy Functions
use existing project
select project 
select javascript
Eslint to catch problems: No
install dependencies with npm: No 
cd functions
yarn 
if yarn error found: npm install -g yarn
firebase init emulators
auth emulator: ENTER
functions Eulator: ENTER
firestore emulator: ENTER
UI: yes
leave empty to use ... : ENTER
download Emulator: yes
install java 
firebase emulators:start