reactjs - Formik Validation in React to add new initialValues while typing in field

Question

I want to do the validation of form in my react application with Formik. I have the fields firstName, lastname, email, phone, address, hobbies. for firstName & lastName (both are required fields) intial values are

 "firstName": "",
 "lastName": "", 

for rest of the fields (optional fields), initial values are

 "infoFields": [
    {
      "fieldType": "",
      "dataType": "",
      "fieldValue": "",
      "isPublic": false
    }
  ] 

Note:- isPublic is a flag for the toggle button to show the field information to other users. So after filling the phone number, address, hobbies, the value should be like this

"infoFields": [
    {
      "fieldType": "PhoneNumber",
      "dataType": "string",
      "fieldValue": "+1234567890",
      "isPublic": true
    },
    {
      "fieldType": "Address",
      "dataType": "string",
      "fieldValue": "honolulu",
      "isPublic": false
    },
    {
      "fieldType": "Hobbies",
      "dataType": "ObjectList",
      "fieldValue": [ "cricket", "listening music" ],
      "isPublic": false
    },
    .....................
  ]

How can we get this formik value on click of submit button to send these data to API.