How can I get a and b out of the array?

I’m pretty new to programming, I was trying to built an API call that I will use in another function but I’m stuck here.
I need to get a and b separately and as value out of this:

import axios from "axios";


async function main() {
await axios 
  .get('https://api.blocknative.com/gasprices/blockprices?confidenceLevels=99', {
    headers: { Authorization: 'key'},
  })
  .then(function (response) {
      const a = response.data.blockPrices[0].estimatedPrices[0].maxFeePerGas;
      const b = response.data.blockPrices[0].estimatedPrices[0].maxPriorityFeePerGas;
      return[a,b]
      });
  };
main().catch(console.error);

How can I do it?
I already take a look at scope,block and destructuring but I really can’t figure a way out.
Thanks for your help!