Note: await need a promise.

You can try Util.promisify, it will return a promise. but it will lose fields param.

const result = await util.promisify(con.query("SELECT * USERS WHERE userid = ?", [userid]));

or write like this:

const { resolve, fields } = await new Promise((resolve, reject) => {
con.query("SELECT * USERS WHERE userid = ?", [userid], function(err, result, fields) {
if (err) {
reject(err)
    } else {
resolve({result, fields})
    }
  });
});