block.js

registerBlockType(name, {
  edit: props => <Editor {...props} />,
  save: props => <Save {...props} />
});

Editor.js

export const Editor = ({attributes}) => {
  const {something} = attributes;
  const [data,setData]= useState({});
  useEffect( () => {
      fetch( `https://hiroy.club/${something}`)
        .then(r => r.json())
        .then(r => setData(r);
  }, [something, setData]);
  return (
      <div />
  );
}