I have just started learning Redux, Having some understanding I tried creating a counter app and the state of my app is not working even after dispatching an action with type. Please share your thoughts.
Here is the source code CODESANDBOX LINK
You'd better use react-redux. See Why Use React Redux?
The process of subscribing to the store, checking for updated data, and triggering a re-render can be made more generic and reusable. A UI binding library like React Redux handles the store interaction logic, so you don't have to write that code yourself.
There is no need to subscribe to the store by yourself. The reason why UI doesn't change even if you dispatch the action is because the App component doesn't re-render to get the latest state from the redux store.
Refactor to this: codesandbox