You provide no dependency array (undefined) to your useEffect. If the component's state changes, then the useEffect will be called again, which sets the state again, and so on.

You can provide an empty dependency array which will cause the useEffect to be called only once.

useEffect(() => {
    getData();
    getData2();
}, []);

Edit: In response to the comments. You can prevent the screens content from rendering until the data has been fetched as follows.

const MyData = () => {
  const [data, setData] = useState();
  const [newData, setNewData] = useState();

  const getData = () => {
    axios.get("url").then(async function (response) {
      setData(response);
    });
  };

  const getData2 = () => {
    axios.get("url").then(async function (response) {
      setNewData(response);
    });
  };

  useEffect(() => {
    getData();
    getData2();
  }, []);
  
  if (!data || !newData) {
     return null
  }
   
  const NewData = () => {
    return (
      <View>
        <Text>{data.name}</Text>
      </View>
    );
  };

  const RewData = () => {
    return (
      <View>
        <Text>{newData.name}</Text>
      </View>
    );
  };

  return (
    <View>
      <NewData />
      <RewData />
    </View>
  );
};