How can I loop through arrays for different users in a database and generate users with same dates?

Question

I have a database similar to this.

[
  {
    name: \'Ben Smith\',
    age: 24,
    dutyDates: [2020 - 12 - 06, 2020 - 11 - 21, 2020 - 10 - 11],
    role: \'st