How I can use multiple hosts in AWX playbook?
I suspect you haven't set up the host in your inventory you can figure out where your hosts are being pulled from with the following command:

ansible-config dump | grep HOST


In practice, you probably just need to create an inventory file with the following content:

[nodes]
node01 ansible_host=IP OF YOUR FIRST NODE HERE!!!
node02 ansible_host=35.228.80.9


Then specify the -i parameter to ansible-playbook:

ansible-playbook -i inventory -k playbook.yml


Depending on your exact use cases it might be more scalable and maintainable to use GCE Dynamic Inventory, although this does require a little bit of extra setup.