let arr = [];
const example = e => {
  arr.push(e);
  console.log(e);
};

Just declare somewhere an array and push the values there.

let arr = [];
const example = item => {
        arr.push(item);
        console.log(arr);
    };

First of all I would recommend to use a function that sends your requests, e.g. sendRequest(). If you access a database or some website you have to declare an async function, because it's unsure, when you get your response back. Your sendRequest function can then return a javascript object either if the api call was successful or not. The keyword await waits, until the promise is resolved.

Now to your question: If your call was successful, just push your result to an outer defined array apiResults, thats it.

const apiResults = [];

async function sendRequest() {
  try {
    const apiResult = await axios.get('https://jsonplaceholder.typicode.com/todos/1');
    const apiSuccess = Boolean(apiResult);
    
    if (apiSuccess) {
      apiResults.push(apiResult);
    }
    return { ok: apiSuccess, data: apiResult }; 
  } catch (err) {
    return { ok: false, data: {} };
  }
}

(async function test() {
  console.log('Before', apiResults);
  const response = await sendRequest();
  console.log('After', apiResults);
})();

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