const options = {method: 'GET', headers: {'x-api-key': '<api-key>'}};

fetch('https://sandboxapi.me-cash.com/v1/ramp/wallet/{walletId}', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

{
  "status": "success",
  "message": "fetch wallet successfully",
  "data": {
    "id": "bb438dfd-535f-4d5c-a9a7-cceb0988d4b3",
    "address": "0xcb9aebd75ee1240e1e6d5a116772123f936ad109",
    "blockChain": "MATIC-AMOY"
  }
}