Community of action means a group of people working together to do something. Just like how you and your friends might work together to build a sandcastle at the beach or help each other on a tricky puzzle, a community of action can be made up of people who all have a common goal.
For example, let's say a group of people in your neighborhood want to clean up the park. They might get together and form a community of action to make this happen. Each person would have a role, like picking up litter or organizing a fundraiser to buy new benches for the park.
When a community of action works together, they can accomplish things that might be too big for just one person. It's like when you and your friends work together, you can build a bigger and better sandcastle than if you tried to build one by yourself.
So, community of action means people coming together to do something, working as a team to achieve their goals.