For obtaining API Key, Auth Domain, Database URL and Storage Bucket follow below mention steps :
Step 1 : Go to Firebase....
Step 2 : If you have a Firebase account, Signin, else SignupStep 3 : Click on Get Started
Step 4 : Click on Create a Project
Step 5 : Enter your project name and tick mark the checkbox to accept terms and conditions
Step 6 : Click on Continue
Step 7 : Select "Set up Google Analytics for my project" and click on Continue
Step 8 : Open Configure Google Analytics dropdown menu
Step 9 : Choose your Google Analytics account or create a new account, and click on Create Project
Step 10 : Click on Continue
Step 11 : Click on Add Firebase to your web app
Step 12 : Enter App nickname
Step 13 : Click on Register app
Step 14 : Click on Continue to Console
Step 15 : Click on Build menu
Step 16 : The Build dropdown menu will open on the left hand side panel, click on Authentication
Step 17 : Click on Get Started
Step 18 : Click on Anonymous
Step 19 : Enable Anonymous
Step 20 : Once done, click on Save button
Step 21 : In build menu on the left hand side panel, click on Realtime databas
Step 22 : Click on Create database
Step 23 : Select Realtime database location by click on dropdown menu and after select click on next
Step 24 : Click on Enable
Step 25 : Click on Rules
Step 26 : Delete the entire code
Step 27 : Now enter the following code, and click on Publish